Cross-Reference to Related Applications

This application is a continuation-in-part of US Patent Application 16/455,975 filed on June 28, 2019, US Patent Application 16/523,805 filed on July 26, 2019 (now US Patent 10,609,797), and US Patent Application 16/824,699 filed on March 20, 2020. This application also claims the benefit of U.S. Provisional Application 62/843,949 filed May 6, 2019, U.S. Provisional Application 62/843,965 filed May 6, 2019. and US provisional application

62/843,949 filed May 6, 2019. All six of the afore-mentioned applications are hereby

incorporated by reference in their entirety herein for any and all purposes.. Background

Technical Field

The present subject matter relates to distribution of direct-current power within a building, including distribution of power to drive lighting.

Background Art The building of infrastructure to distribute electrical energy from large generators run by utilities (either public or private entities) to homes and businesses where the electricity was consumed began in the nineteenth century. Two competing technologies emerged for how the electrical energy should be distributed. One camp, led by Thomas Edison and General Electric, promoted the use of direct current (DC), while another camp, led by Nikola Tesla and George Westinghouse, promoted the use of alternating current (AC). As is the case with many competing technology standards since that time, the battle became quite heated due the large potential profits that were at stake, but by the dawn of the twentieth century, AC power generation and distribution had clearly won, with a vast majority of electrical generation and distribution built over the next 100 years supporting AC, not DC. Thus, the ubiquitous wall outlet in the United States provides AC power and a vast majority of devices that are electrically powered are designed to use AC power unless they use batteries (which provide DC power as their primary power source). In the United States, 120 volt (V) AC power is commonly distributed to wall outlets using 14 AWG (American wire gauge) which can safely carry up to 15 amps (A) of current although larger wires allowing higher currents are also commonly used, especially 12 AWG wiring supporting up to 20 A. This means that devices requiring up to about 1800 watts (W) can utilize a standard power plug. But while heat-generating devices (e.g. hair dryers, microwave ovens, and space heaters) and devices utilizing powerful motors (e.g. refrigerators, kitchen mixers, and large fans) may approach this limit, other devices that plug into a wall outlet use well below the maximum power available, with many devices consuming 100 W or less and most utilizing under 500 W.

But as the electricity market continues to evolve towards more sustainable solutions with renewable energy and energy storage, local distribution of power in buildings may eventually transform from alternating current (AC) to direct current (DC). This is at least partly due to emerging technologies like improving photo-voltaic electrical generation and improved batteries for energy storage which both operate on DC; it is significantly more efficient to transfer and store generated DC power directly. Another reason for the emergence of DC power distribution is that the end consumption of energy by DC-powered devices continues to grow. One example of this is the emergence of light-emitting diode (LED) based lighting. Lighting has historically been the second biggest consumer of energy after heating, ventilation, and air-conditioning (HVAC) and traditional incandescent and fluorescent lighting can natively utilize AC power. LEDs, however, natively utilize DC power, so LED-based lighting today currently requires AC/DC conversion to operate when powered from the traditional AC power grid, causing inefficiency, heat generation, quality issues when used with traditional dimming devices, and reduced lifetime due to limited life of critical electric components. Operating LED-based lights directly from DC would be more efficient.

The third largest consumers of energy in buildings, especially homes, are electronic devices. Electronic devices are on track to overtake lighting in terms of consumption, especially due to the growth of the internet of things (IoT) and the higher efficiency of LED-based lighting. Electronic devices generally utilize DC power which is generated from the distributed AC power by an AC to DC converter which may be embedded inside the device or provided by an external power supply which has a standard AC plug and a separate cable to provide DC power to the electronic device. While a wide array of connectors may be used for the DC power connection to the electronic device, in many cases a universal serial bus (USB) connector is used as the DC power connector, even if no data connection is supported. One emerging trend for DC distribution for information technology (IT) equipment, telephones, cameras, and more recently, lighting, is power over Ethernet (PoE). PoE comes in several flavors that mainly are differentiated by power capacity. The Institute of Electrical and Electronics Engineering (IEEE) standard 802.3af was the first PoE standard to be adopted. It specified a way to provide Ethernet data and power up to 15.4 watts (W) through a single cable which was ideal for telephones. IEEE 802.3at come later with capacity up to 30W and most recently IEEE 802.3bt allows up to 100 to be provided at voltages up to 57 V. There are also proprietary flavors of PoE such as Cisco Systems UPoE.

Circuitry to dim lighting is well known and has been widely used for many years.

Traditional light sources, such as incandescent light bulbs, could be dimmed using a phase-cut dimmer. Such dimmers are widely available and are commonly installed in a lighting circuit in place of a traditional on/off switch. Phase-cut dimmers are typically triac-based and come in various topologies and designs, but they work by cutting off a portion of the alternating-current (AC) waveform to reduce the energy delivered to the light bulb. This worked every well for incandescent bulbs which effectively integrate the AC waveform and have a slow response time which eliminates any flickering. Lighting based on light-emitting diodes (LEDs), however need to include special circuitry to detect the intended dimming level of a traditional phase-cut dimmer to be able of function properly. Some LED drivers are designed to detect the amount of phase-cut on the AC line and then control the brightness of the LEDs using a variable current or a pulse-width modulated signal.

Other techniques for controlling the brightness level of LED-based lighting are also known. Some systems use an analog control signal to communicate a brightness level to an LED driver, such as a signal that varies from 0 volts (V) to turn the lighting off, to 10 V to turn set the lighting to full brightness. Another technique uses a digital addressable lighting interface (DALI) which is a two-way communication system with defined commands for LED drivers. This allows a controller to communicate with individual LED drivers and set the desired brightness level.

Regardless of how the dimming level is controlled, using a phase-cut dimmer on the AC power or using an analog signal or digital messages to the LED driver, there are two basic ways to control the brightness of an LED itself. In one approach, referred to as constant voltage (CV) dimming, an LED load is designed to receive specific DC voltage and a CV-based LED driver will provide whatever current will flow through the LED or LED array being driven. The other approach to drive an LED load is the constant current (CC) method, where the LED driver has a fixed current and will let the voltage level rise of fall dependent upon the LED load. Brightness of the LED can be controlled by modulating the power delivered by the driver to the LED load. Because LEDs have a non-linear response to voltage, analog modulation of the voltage for dimming is not commonly used with a CV driver. To dim an LED load with a CV driver, the voltage is commonly modulated using pulse width modulation (PWM) or pulse density modulation (PDM), both of which affect the percentage of a given time period that the voltage is applied to the LED load which digitally modulates the power delivered. The time period is typically chosen to be short enough that most people can’t detect any flickering, such as 16 milliseconds (ms) or less, with the PWM or PDM modulation being performed for each time period. So for example if a 25% brightness is desired, a PWM system may repeatedly turn the voltage on for 4 ms and then turn off the voltage for 12 ms before turning the voltage back on again and repeating.

While a CC driver can use PWM or PDM to modulate the current delivered to the LED load, it is common for a CC driver to dim the LED load by changing the DC current level delivered to the LED load, which is an analog modulation of the power delivered. This technique for dimming an LED has an advantage over PWM and PDM it eliminates high frequency flicker from the LED's that can cause health issues such as migraines.

Traditionally, LED drivers receive the incoming power from an AC mains line or in rare cases from a Direct Current source. One emerging trend for DC distribution for information technology (IT) equipment, telephones, cameras, and more recently, lighting, is power over Ethernet (PoE). PoE comes in several flavors that mainly are differentiated by power capacity. The Institute of Electrical and Electronics Engineering (IEEE) standard 802.3af was the first PoE standard to be adopted. It specified a way to provide Ethernet data and power up to 15.4 watts (W) through a single cable which was ideal for telephones. IEEE 802.3 at come later with capacity up to 30W and most recently IEEE 802.3bt allows up to 100W to be provided at voltages up to 57 V. There are also proprietary flavors of PoE such as Cisco Systems’ UPoE, Linear Technology’s LTPoE, and Microsemi’s PowerDsine solution. Devices that source PoE power are known as power sourcing equipment (PSE) and a device that consumes PoE power is known as a powered device (PD).

Some PSEs simply provide a set amount of power at all times, with no negotiation, which may be referred to as passive PoE. Passive PoE is simple and inexpensive but can lead to situations where a PD and PSE are not compatible with each other with no indication of an error other than the fact that the PD does not operate properly. In some cases, this can even lead to damage to the PSE or PD. A PD that is compliant with IEEE PoE standards includes a 25kQ (kilohm) resistor between the powered pairs. Additional information about the power

requirements of a PD may be determined providing a classification voltage to the PD and measuring the resultant current, and/or by using Link Layer Discovery Protocol (LLDP) over the Ethernet connection to determine the power requirements of the PD.

Brief Description of the Drawings

The accompanying drawings, which are incorporated in and constitute part of the specification, illustrate various embodiments. Together with the general description, the drawings serve to explain various principles. In the drawings:

FIG. 1 shows a stylized view of a home utilizing an embodiment of a power distribution system;

FIG. 2A shows block diagram of an embodiment of the power distribution system;

FIG. 2B shows block diagram of an embodiment of circuitry of an edge device;

FIG. 3 A is perspective view of a back of an embodiment of an edge device;

FIG. 3B is a front view of the embodiment of the edge device;

FIG. 4 is a front view of an alternate embodiment of an edge device;

FIG. 5 is a flowchart of an embodiment of a method of distributing power;

FIG. 6 shows a block diagram of an embodiment of a power-over-Ethernet (PoE) system; FIG. 7 shows a more detailed block diagram of embodiments of two powered devices (PDs) of the PoE system;

FIG. 8 shows a more detailed block diagram of an embodiment of power system equipment (PSE) of the PoE system;

FIG. 9 shows waveforms of PoE negotiation for an IEEE compliant PD;

FIG. 10 shows waveforms of PoE negotiations for an embodiment of a PD that is consistent with IEEE PoE standards, but provides additional capability;

FIG. 11 is a flowchart of an embodiment of negotiating for an LED driver in a PoE system;

FIG. 12 shows a block diagram of an embodiment of a system providing constant current (CC) drive for a constant voltage (CV) load;

FIG. 13 shows voltage and current waveforms for the embodiment of FIG. 1;

FIG.14 shows a block diagram of an alternative embodiment of a system providing CC drive for a CV load;

FIG. 15 shows voltage and current waveforms for the embodiment of FIG. 3; FIG. 16 shows a block diagram of an embodiment of a system providing CC drive for a CV load using a load identification device (LID);

FIG. 17 shows a block diagram of an embodiment of a system providing CC drive for a CV load using centralized power source;

FIG. 18 is a flowchart of an embodiment of a method for providing constant current (CC) drive for a constant voltage (CV) load; and

FIG. 19 is a flowchart of an embodiment of a method for universal driving of an LED load.

Detailed Description

In the following detailed description, numerous specific details are set forth by way of examples in order to provide a thorough understanding of the relevant teachings. However, it should be apparent to those skilled in the art that the present teachings may be practiced without such details. In other instances, well known methods, procedures and components have been described at a relatively high-level, without detail, in order to avoid unnecessarily obscuring aspects of the present concepts. A number of descriptive terms and phrases are used in describing the various embodiments of this disclosure.

Power Distribution to Edge Devices

A transition of infrastructure from AC to DC provides an opportunity for major changes in paradigm. It is currently very difficult for innovative home power distribution solutions to gain a foothold due to the regulatory environment (i.e. electrical codes) and the existing base of contractors and electricians which are rooted in the traditional infrastructure.

Embodiments are described herein that utilize existing cost-effective components and technologies but apply them in an innovative way to provide DC power within a building while easily co-existing with traditional AC power distribution to create a transition path which allows more and more devices to utilize native DC power. DC power, as the term is used herein, may include embodiments where the current is not continuous, but may vary over time, including pulse-width modulated DC power where the current is switched on and off at various frequencies and/or duty-cycles. One issue with traditional technologies is that power over Ethernet (PoE) cannot provide as much power as common electronic devices, such as televisions, computers, and stereo systems, require. Many versions of PoE are not even able to provide as much power as common connectors, such as the USB-C connector (capable of up to 100 W), can provide. Embodiments of a device, hereinafter referred to as an edge device, may receive DC power through a single cable, such, but not limited to, what is commonly called an Ethernet cable, having several conductors of relatively small gauge (i.e. smaller than a traditional AC power distribution cable which is 14 AWG or larger) and provide a connector to be used by a DC-powered device. The edge device may be sized to fit into a standard single-gang electrical junction box and include a standard connector accessible when installed, such as a USB connector (e.g. a standard or micro USB-A connector or a USB-C connector), a barrel connector, or an RJ-style connector that can be used by a DC-powered device as its power source.

Any type of cable may be used to distribute the DC power to the edge device (i.e. the distribution cable), but in at least some embodiments a cable designed for use with an Ethernet network may be used. Several types of Ethernet cables are defined including, but not limited to, category 3 (cat3), category 5 (cat5), category 5e (cat5e), category 6 (cat6), and category 7 (cat7) cables. Ethernet cables may be specified by the ANSI/TIA/EIA-568 standard, which is incorporated by reference herein. The most recent version of this standard (version D) can be purchased at https://global.ihs. com/doc_detail.cfm?item_s_key=00378460 as of the date of filing of this application. In other embodiments, the distribution cable may be any other type of cabling, such as cabling designed for telephony use, lamp cord, or other types of insulated wire. The distribution cable can have any number of conductors, but typically may include 2-8 conductors having a size of 16 AWG or smaller. Ethernet cables typically have 8 conductors of 22-24 AWG.

In some embodiments, a different mechanical form-factor may be used for the edge device. A traditional electrical junction box may not be required, allowing other form factors to be used. In some embodiments, the edge device may be directly mountable into a hole cut into drywall material as the isolation requirements for high power class 1 power doesn’t apply and Ethernet could be plugged in directly from behind a drywall. In other embodiments, the edge device may be configured to fit into a cavity having different dimensions than a standard electrical junction box, and may be smaller, larger, and/or have a different aspect ratio.

Some embodiments of the edge device may accept power to be provided by a standard PoE injector or a PoE enabled switch device through a standard RJ-45 Ethernet connector. In other embodiments, an AC-to-DC power supply or a DC power source (e.g. a battery, a DC-to- DC converter, or a photovoltaic panel) may be used to provide power to the distribution cable powering the edge device and the distribution cable may connect to the edge device using any type of connector, including, but not limited to, a barrel connector, a USB connector, an RJ11/RJ14/RJ25 connector, an HDMI connector, or a pin and socket connector. In some embodiments, contacts may be provided by the edge device to allow the wires of the distribution cable to be soldered or otherwise attached to the edge device (e.g. screw attachment or spring- loaded contacts).

Some edge devices may also provide communications capability, such as an RJ-45 Ethernet network connector or an HDMI connector to provide digital video. Depending on the embodiment, the same connector may be used to provide DC power and the communications capability, or separate connectors may be used. In at least one embodiment, the edge device communicates over a wired network through the distribution cable used to provide the edge device with DC power, and the edge device communicates with other devices wirelessly, using any version of IEEE 802.11, any version of IEEE 802.15, any version of Bluetooth, or any other wireless communication protocol using any frequency, including radio-frequency signals and optical signals. The edge device may communicate wirelessly with another device directly, or through intermediate devices such as in a wireless mesh network, depending on the embodiment. Other embodiments may provide an interface to a peripheral, such as a printer interface, a hard drive interface, an audio adapter to provide audio to an amplifier or speaker, or a display, to provide network devices access to the peripheral as a network resource. In another embodiment, a data storage device, such as a solid-state drive or a hard drive may be included in the edge device to provide network attached storage (NAS) to network devices. In at least one

embodiment, the edge device may include an Ethernet to USB adapter, so that a USB device plugged into the edge device could show up as an Ethernet device over the distribution cable. In some embodiments, the positions of the edge devices may be used to pinpoint the location of other devices using wireless positioning systems.

In some embodiments, a battery, fuel cell, supercapacitor, or other energy storage device may be coupled to the edge device. Non-limiting examples of where the energy storage device may be located include integrated into the edge device, co-located with the edge device in a junction box, located its own receptacle in the wall near the edge device, external to the edge device and electrically coupled to the edge device by a cable other than the distribution cable. A battery used as such may be based on any battery chemistry, including, but not limited to, zinc- air, lead-acid, lithium-ion, or lithium-polymer, and may or may not be rechargeable. In embodiments, the energy storage device may allow the edge device to source more power than it is receiving for a period of time, acting as a power cache. As a non-limiting example, a rechargeable battery coupled to the edge device may allow the edge device to provide 100 W of power to charge a notebook computer in one hour even though, even though the edge device is only receiving 60 W of power through its attached distribution cable. As another non-limiting example, an edge device receiving 30 W of power through its attached distribution cable may be able to source 60 W of power by using an attached fuel cell to augment the power received through its distribution cable until the fuel in the fuel cell is depleted. If the energy storage device is rechargeable, the edge device may have bimodal power capability, sourcing a first level of power not exceeding the power provided through the distribution cable if the energy storage device is discharged, and a second, higher level of power using energy from the energy storage device to supplement the power provided through the distribution cable. As another non-limiting example, the edge device may provide a USB-C connector for power to a load that can provide up to 100 W if the attached rechargeable battery is charged, but may be limited to the 30 W available from its distribution cable once the batter is discharged. Once the load drops below 30 W, the power received from the distribution cable which is not provided to the load may be used to recharge the battery. Additionally, the attached energy storage device may allow the edge device to continue to provide power to its load even if there is an interruption of the power received through the distribution cable due to a power failure, overload of the power supply supporting the distribution cable, or other cause.

In some embodiments, a connector used to provide power to a load may be integrated with the energy storage device. The energy storage device with integral connector maybe removable from the edge device and may be used to provide power to a load, such as a computer, a television or an amplified speaker, at a location separated from the edge device. This may allow for easy mobility of devices that don’t include an integrated battery. In some embodiments, the removable battery may be recharged while removed from the edge device to allow faster charging from an alternative power source. In some embodiments, a removable energy storage device may be replaceable while the edge device is providing power to its load to allow the edge device to provide high power for a longer period of time. In such edge devices, a second smaller energy storage device may be integrated into the edge device (or otherwise coupled to the edge device) to allow continuous power during the replacement of the removable energy storage device. To help minimize the issue of the removable energy storage device being misplaced, some embodiments, may include a button on the edge device or on the receptacle for the energy storage device that triggers an alert (e.g. audible noise or flashing light) by activating a transducer on the removable energy storage device. In some embodiments, edge devices with energy storage devices may be linked together with wires other than the distribution cable to allow stored energy to be shared between edge devices. This capability may be used to provide high power output for a longer period of time than could otherwise be sustained or to allow the energy storage device in one edge device to be replaced while providing continuous high power output. In some embodiments, a mesh of edge devices may be created allowing stored energy from a plurality of edge devices to be provided to a particular edge device, even if some of them are not directly connected. This would allow the edge devices to act as a mini power-grid. In some embodiments, a separate controller may be used to communicate with the edge devices to manage the grid and how energy is transferred between edge devices, but in other embodiments, software running on one or more of the edge devices may be able to control the grid.

In some embodiments, energy storage devices may allow edge devices to continue to provide the minimum-rated power even if the power available through their distribution cable is lower than expected or interrupted (i.e. a power outage). In some cases, the power source for the distribution cables may not be able to provide the full rated power to every edge device. One example of this is a photovoltaic device which may have variable power output depending on the amount of sunlight it is receiving. Energy storage devices may allow the edge device to continue to provide power when the sun is temporarily occluded by a passing cloud or even to continue to provide power after the sun sets. Use of a mesh of edge devices with attached energy storage in a photovoltaic system may allow for a significant amount of stored energy which may allow the edge devices to continue to source power throughout the night. In another example, a power supply used to provide power the distribution cables may have a total power limit below that of the combined power limits of each individual distribution cable. Use of energy storage devices may allow the edge devices to continue to provide power even when the total power of their combined loads exceeds the total power limit of the power supply.

Some embodiments of the edge device may include a DC-to-AC converter or inverter and a traditional AC power outlet (e.g. a NEMA 5-15) to allow the edge device to provide power to conventional AC-powered devices. In some embodiments, an energy storage device may be used in conjunction with the DC-to-AC converter to allow short-duration high-power devices such as toasters, hair dryers, or microwave ovens, to be powered by the edge device.

In some embodiments, the edge device may provide wireless power using electric field induction, magnetic inductive coupling, magnetic resonant coupling, radio-frequency

transmission, laser transmission, or any other technology for wireless transmission of power between two devices. Non-limiting examples of magnetic inducting coupling for wireless power transmission include a Qi interface as defined by the Wireless Power Consortium and AirFuel Inductive charging as defined by the AirFuel™ Alliance. A non-limiting example of magnetic resonant coupling is an AirFuel Resonant system as defined by the AirFuel Alliance.

Reference now is made in detail to the examples illustrated in the accompanying drawings and discussed below.

FIG. 1 shows a stylized view of a home 100 utilizing an embodiment of a power distribution system. While a home 100 is shown, the concepts and devices could be used in any type of commercial, industrial, or residential building. The home 100 includes several rooms, including a utility closet 101, a bedroom 102, a kitchen 104, a living room 106, and an office 108. The home receives power from a utility through a utility line 130. The power from the utility can be any type of electrical power, but may be single phase, two phase, or three phase AC power in various embodiments. The home 100 also includes a solar panel 134 to generate DC power locally.

The utility power line 130 may be coupled, through cable 132 which may be hidden in the walls of the home 100, to a DC distribution unit 140 which is located in the utility closet 101 in this example, but could be located anywhere in a building. The DC distribution unit 140 may convert the AC power from the utility to DC power. The solar panel 134 may also be coupled, through cable 136, to the DC distribution unit 140.

The DC distribution unit 140 may provide DC power to one or more edge devices 152- 158 through distribution cables 142-148. The distribution cables 142-148 may be routed through the walls or other structure of the home 100 to hide them from view. The distribution cables 142- 148 may be any type of cable with any number of conductors of any size, depending on the embodiment. In some embodiments, the distribution cables 142-148 may utilize cables targeted of use with Ethernet networking and may include 8 conductors of 22-24 AWG. Any number of conductors in the distribution cables 142-148 may be used to carry the electrical power but in some cases the power may be distributed in accordance with power-over-Ethernet consistent with IEEE 802.3af, IEEE 802.3at, or IEEE 802.3bt. The edge devices 152-158 may include a connector positioned to be hidden within the wall while the edge device is mounted into the wall that couples to the distribution cables 132-148.

Edge devices 152-158 may be configured to be mounted in a standard single-gang electrical junction box in the walls of the home 100, although other embodiments may be configured to mount on the outside of a wall or as a separate device to sit on the floor or a piece of furniture. The edge devices 152-158 may also include an accessible connector, that is a connector positioned to be exposed while the edge device is mounted into the wall, to provide DC power to another device, such as the example devices shown. Clock radio 122 is coupled to edge device 152, coffee maker 124 is coupled to edge device 154, lamp 126 is coupled to edge device 156, and monitor 128 is coupled to edge device 158.

In some embodiments, additional cables (not shown in FIG. 1) may be used to couple edge devices 152-158 directly to other edge devices to create a mesh of edge devices. This may allow an edge device to provide more power to it load, such as coffee maker 124, than it could otherwise source from its single connection to the DC distribution unit 140. In some

embodiments, the edge devices 152-158 may include energy storage devices which can provide additional power for limited periods of time to augment the power received through the edge devices’ 152-158 distribution cable 142-148.

FIG. 2A shows block diagram of an embodiment of the power distribution system 200. The system 200 includes a power distribution unit 240, which may be similar to the DC distribution unit 140 of FIG. 1. The power distribution unit 240 receives power from a utility, a local power generator (e.g. a solar cell or windmill), or local energy storage, and distributes DC power over a distribution cable 242 to an edge device 250. One power distribution unit 240 may be able to provide power to any number of edge devices, depending on the embodiment. The power distribution unit 240 may have intelligent control to determine where to best draw power at any given time and may also include control of charging a bank of batteries, using low cost power (e.g. local solar cells or off-peak utility power) to charge the batteries and using stored battery power during peak load periods.

The edge device 250 may include a first connector 252 to mate with the distribution cable 242 and receive DC power and a second connector 254 to provide power to a load 270 through a power cable 274. The first connector 252 may be positioned to be hidden within the wall while the edge device 250 is mounted into the wall and the second connector 254 may be positioned to be exposed and accessible to a user while the edge device 250 is mounted into the wall. The first connector 252 and second connector 254 may be any type of connector, depending on the embodiment, but in some embodiments, the first connector may be an RJ-45 connector compatible with an Ethernet cable using power-over-Ethernet (PoE) and the second connector 254 may be a communication connector of some type, such as, but not limited to, a USB-C connector, a USB -A connector, an HDMI connector, or an RJ-type connector. In some embodiments, communication circuitry (which may be a part of circuitry 255) may be coupled between the first connector 252 and the second connector 254 to provide for data communication between the two connectors 252, 254. The communication circuitry may be any type of circuitry including circuitry to perform translation between data protocols, but in some embodiments, the communication circuitry may consist only of passive components, such as, but not limited to conductors, resistors, capacitors, and/or inductors. The edge device 250 may be able to provide any amount of DC power to the load 270, depending on the embodiment, but in some

embodiments, up to 100 W may be provided to the load.

The edge device 250 includes circuitry 255 to manage the power received through the first connector 252 and provided through the second connector 254. The circuitry 255 may convert the voltage level, modulation, or other characteristics of the received DC power before it is sent to the load 270. For example, the receive power may have a voltage level of around 50 V which is commonly used for PoE, but the output power provided to the second connector 254 may be limited to 5V if a USB-A connector is used, so the circuitry 255 may include voltage regulation such as a DC-to-DC converter. In other embodiments, current regulation may be included in the circuitry 255 and in yet other embodiments, modulation, such as pulse-width modulation may be performed by the circuitry 255 on the power provided to the second connector 254. In some embodiments, such as the embodiment shown in FIG. 2B, the circuitry 255 may include a processor 280 and memory 282 storing instructions 284 for the processor 280. A network interface 286 providing for communication with other edge devices through the other connection 258 and/or with the power distribution unit 240 through the first connector 252 may also be included.

The edge device 250 may include energy storage 260 in some embodiments. The energy storage 260 may include one or more batteries (rechargeable or non-rechargeable), one or more capacitors (including so-called super-capacitors), a fuel cell, or any other type of energy storage 260. The energy storage 260 may be integrated into the edge device 250 or may be separate from the edge device 250 and may be removable in some embodiments. The circuitry 255 may manage the energy storage device 250 to determine when to charge and when to draw power from the energy storage device 260. In some embodiments, the energy storage 260 may be housed in an enclosure 262 that is removeable from the edge device 250 that may also include a transducer 264, such as an LED, a speaker, or a vibrator, and alert circuitry 266, coupled to the transducer 264 to receive a wireless signal from the circuitry 255 and activate the transducer 264 to emit light, make a sound, or vibrate, in response to receiving the wireless signal. The circuitry 255 may include a user input device 288, such as a button or any other type of input, and notification circuitry (which may be the same as the network interface 286 or a separate wireless transmitter), coupled to the user input device 288, to send a wireless signal in response to an input received from the user input device 288 to help a user find the energy storage 260 if it has been removed from the edge device 250.

The edge device 250 may have one or more other connections 258 (which may coupled through connectors) which allow the edge device to connect to other edge devices and/or other energy storage devices. The edge device 250 may be a part of a mesh of edge devices allowing power to be provided from another edge device to the edge device 250 or vice versa. The circuitry 255 may manage the participation of the edge device 255 in the mesh. Thus, the circuitry 255 may control the flow of DC power from the other connection 258 to the second connector 254 and on to the load 270 and/or the flow of DC power between the other connection 258 and the energy storage 260.

In some embodiments, the circuitry 255 may include a network interface 286 coupled to the other connection 258 and a processor 280 coupled to the network interface 286. The processor 286 may be programmed to communicate with at least one other processor through the network interface to determine whether to send or receive DC power through the other connection 258 and to send DC power from the energy storage device 260 through the other connection at a first time in response to a determination to send DC power. The processor may further be programmed to determine how to utilize the DC power received from the other connection 258 based on at least one of a state of the energy storage 260 or a power requirement from the load 270 coupled to the second connector 254, in response to a determination to receive DC power and send at least some of the DC power received from the other connection 258 to the energy storage 260 at a second time. The processor may also be programmed to send at least some of the DC power received from the other connection 258 to the second connector 254 at a third time.

In embodiments of some systems 200, the processor 280 may be programmed to determine how to utilize the DC power received from the power distribution unit 240 through the first connector 252 based on at least one of a state of the energy storage 260 or a power requirement from the load 270 coupled to the second connector 254. The processor 280 may then send a first portion of the DC power received through the first connector 252 to the energy storage 260 and send the rest (i.e. a remaining portion) of the DC power received through the first connector 252 to the load 270 through the second connector 254. This may be done simultaneously or sequentially. The power distribution unit 240 and the edge device 250 may be in communication with each other in some embodiments. The communication may take place through the distribution cable 242 and may use any communication protocol, but in some cases, an IEEE 802.3 (i.e. Ethernet) protocol, may be used over two or more twisted pairs in an Ethernet cable used as the distribution cable 242. In at least one embodiment, power delivery in compliance with IEEE power over Ethernet standards is negotiated for power delivered over the twisted pairs used for 10BASE-T or 100BASE-TX (mode A) while power for charging the energy storage 260 is delivered over the other two twisted pairs in a way that may not be compliant with IEEE standards. This may be used in conjunction with embodiments disclosed in related US Patent Application #16/455,975 entitled“Remote Dimming of Lighting” filed on June 28, 2019, which is incorporated by reference herein. The power received on the data pairs may be used to power the load 270, which may be LED lighting, and the power may be modulated by the power distribution unit 240 to control the brightness of the lighting. If the edge device 250 detects that power is no longer being supplied by the power distribution unit 240, it may then supply power from the energy storage 260 back to the power distribution unit 240 which can use that power it receives from the edge device 250 and/or other edge devices to continue to function and to route the power to the appropriate edge devices for emergency lighting. The detection of the power loss event may take place by the circuitry 255 in the edge device 250 by recognizing that power is no longer being supplied through one or more pins of the first connector 252, or by receiving an alert through the distribution cable 242 from the power distribution unit 240. The alert can take the form of a simple signal provided through the distribution cable (e.g. pulling a pin high or low) or by sending a message using a communication protocol (e.g. Ethernet or RS-232) through the distribution cable.

FIG. 3 A is a back perspective view and FIG. 3B is a front view of an embodiment of an edge device 300. The edge device 300 may be comparable to the edge device 250 of FIG. 2A and is adapted to fit into a single-gang electrical junction box, as described by the National Electrical Manufacturers Association (NEMA) WD 6-2016 specification, although other embodiments may have other form-factors. The NEMA WD 6-2016 specification, which is incorporated by reference herein, could be downloaded from

https://www.nema.org/Standards/Pages/Wiring-Devices-Dimen sional-Specifications.aspx as of the date of filing of this application. An edge device that has a size and shape to fit into a single gang electrical box may have a body with maximum dimensions of about 4.45 centimeters (cm) by about 7.14 cm and a depth of about 9 cm or less ( 1.75 x 2.82 x 3.5 inches) and having a mounting yoke 302 with mounting holes 304 spaced about 8.33 cm (3.28 inches) apart although some embodiments may be somewhat larger. The edge device 300 includes a first connector 310 on the back to mate with a distribution cable to receive power. The power may be DC power and may be consistent with power-over-Ethemet (PoE) in some embodiments. In the embodiment shown, connector 310 is an RJ-45 socket compatible with PoE. The front of the edge device 300 includes at least a second connector which is accessible while the edge device 300 is mounted into a wall, with this embodiment including two USB-C sockets 320 and two USB-A sockets 330. In embodiments, the data capabilities of the USB-C sockets 320 and USB-A sockets 330 may or may not be used, with some embodiments only using the sockets 320, 330 to provide DC power. The USB-C sockets 320 may be able to provide up to 100 W of power to a load device in some embodiments but the USB-A sockets 330 may be limited to lower power loads, such as 15 W.

FIG. 4 is a front view of an alternate embodiment of an edge device 400. The back of edge device 400 may be identical or similar to the back of edge device 300 or may be different with additional connections, depending on the embodiment. The edge device 400 receives DC power from a distribution cable and provides DC power through the two USB-C sockets 420 on the front. In addition, the edge device 400 includes DC-to-AC conversion circuitry (e.g. an inverter) to generate 1 lOVAC power to provide to outlet 450. In some embodiments, the current capability of the outlet 450 may be lower than a traditional 15A outlet and some embodiments, may include a circuit breaker and/or overload indicator on the edge device 400.

Aspects of various embodiments are described with reference to flowchart illustrations and/or block diagrams of methods, apparatus, systems, and computer program products according to various embodiments disclosed herein. It will be understood that various blocks of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions.

These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the function/act specified in the flowchart and/or block diagram block or blocks. The computer program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

The flowchart and/or block diagrams in the figures help to illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products of various embodiments. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

FIG. 5 is a flowchart 500 of an embodiment of a method of distributing power. The flowchart 500 begins by receiving 510 direct-current (DC) power from a source. The DC power may be continuous, varying, pulse-width modulated, or switched, or otherwise controlled, depending on the embodiment. The power may be received over a cable with conductors smaller than 14 AWG and may be limited to a safe voltage, current, and/or power level under safety rules from agencies such as Underwriters Laboratories (UL), International Electrotechnical Commission (IEC), CSA Group, or other private or governmental organizations. In some embodiments, the voltage may be kept under 42.4 V and/or the power may be kept under 100 W. In some embodiments, the power may be received from a power-over-Ethernet (PoE) cable.

The flowchart 500 continues with providing DC power 520 to a communications connector, such as a USB connector, an HDMI connector, an RJ style connector, or other connector standardized for carrying communication data as well as having the capability to provide power. In some embodiments, a check may be made to see if a load connected to the communications connector is attempting to draw more power than can be provided by the source 530. If the source power is adequate to provide the desired load, the load current is provided 540 from the source current. In some embodiments, a conversion of the voltage or current level and/or a modulation of the DC power may be done to convert the source current to the load current. In at least one embodiment, a standard AC waveform may be generated from the source current and provided through a standard NEMA outlet instead of or in addition to providing power to the communication connector.

In some embodiments, an energy storage device, such as a battery, may be charged 550 from the DC power received. If it is determined that the load current is greater than the current available from the source 530, the availability of energy storage 560 may be checked. The energy storage may be local or remote. If energy from the energy storage is not available, whatever load current can be provided may be provided 540 to load from the source, although other embodiments may shut off the current to the load if the desired current cannot be provided. If energy is available from the energy storage device 560, current from the energy storage device may be used to augment the current from the source to provide 570 current to the load.

Examples of various embodiments Power Distribution to Edge Devices are described in the following paragraphs:

Embodiment Al. An apparatus comprising: an energy storage device; a mechanical structure configured to hold the energy storage device and mount into a wall of a building; a first connector positioned to be hidden within the wall while the apparatus is mounted into the wall; a second connector, coupled to the energy storage device, and positioned to be exposed while the apparatus is mounted into the wall; and charging circuitry, coupled to the first connector and the energy storage device, to provide direct-current (DC) power received from the first connector to the energy storage device.

Embodiment A2. The apparatus of embodiment Al, further comprising

communication circuitry coupled between the second connector and the first connector to provide for data communication between the second connector and the first connector.

Embodiment A3. The apparatus of embodiment A2, wherein the communication circuitry consists of only passive components.

Embodiment A4. The apparatus of any of embodiments Al through A3, further comprising a data storage device coupled to the second connector to provide data storage for an external device coupled to the second connector. Embodiment A5. The apparatus of any of embodiments A1 through A4, wherein the energy storage device comprises a rechargeable battery.

Embodiment A6. The apparatus of any of embodiments A1 through A5, wherein the energy storage device comprises a capacitor.

Embodiment A7. The apparatus of any of embodiments A1 through A6, wherein the mechanical structure has a size and shape to fit into a single gang electrical box.

Embodiment A8. The apparatus of any of embodiments A1 through A7, wherein the second connector is compliant with at least one USB connector mechanical specification.

Embodiment A9. The apparatus of any of embodiments A1 through A8, wherein the second connector is compliant with a female USB-C connector mechanical specification.

Embodiment A10. The apparatus of any of embodiments A1 through A7, wherein the second connector is an RJ-45 socket.

Embodiment A11. The apparatus of embodiment A10, wherein the apparatus is compliant with an IEEE power over Ethernet standard as power sourcing equipment.

Embodiment A12. The apparatus of any of embodiments A1 through A11, further comprising a DC-to-DC converter coupled between the energy storage device, which provides power at a first voltage, and the second connector to provide DC power to the second connector at a second voltage that is different than the first voltage.

Embodiment A13. The apparatus of any of embodiments A1 through A7, further comprising inverter circuitry coupled to the energy storage device and the second connector to provide alternating-current (AC) power to the second connector.

Embodiment A14. The apparatus of embodiment A13, wherein the second connector is compliant with standard to provide AC power.

Embodiment A15. The apparatus of any of embodiments A1 through A14, wherein the first connector is an RJ-45 socket.

Embodiment A16. The apparatus of any of embodiments A1 through A15, wherein the apparatus is compliant with an IEEE power over Ethernet standard as a powered device.

Embodiment A17. The apparatus of any of embodiments A1 through A16, wherein the energy storage device is removable from the mechanical structure without tools.

Embodiment A18. The apparatus of any of embodiments A1 through A17, further comprising an enclosure holding the energy storage device, the enclosure removable from the mechanical structure without tools and further comprising: a transducer; and alert circuitry, coupled to the transducer, to receive a wireless signal and activate the transducer in response. Embodiment A19. The apparatus of embodiment A18, further comprising: a user input device; and notification circuitry, coupled to the user input device, to send the wireless signal to the alert circuitry in response to an input received from the user input device.

Embodiment A20. The apparatus of any of embodiments A1 through A19, further comprising a third connector coupled to the to the charging circuitry, wherein the charging circuitry is configured to also provide direct-current (DC) power received from the third connector to at least one of the energy storage device or the second connector.

Embodiment A21. The apparatus of any of embodiments A1 through A20, further comprising a third connector coupled to the to the charging circuitry, wherein the charging circuitry is configured to also provide direct-current (DC) power from the energy storage device to the third connector.

Embodiment A22. The apparatus of any of embodiments A1 through A21, further comprising a third connector coupled to the to the charging circuitry, the charging circuitry comprising: a network interface coupled to the third connector; a processor coupled to the network interface and programmed to: communicate with at least one other processor through the network interface to determine whether to send or receive DC power through the third connector; send DC power from the energy storage device through the third connector at a first time in response to a determination to send DC power; determine how to utilize the DC power received from the third connector based on at least one of a state of the energy storage device or a power requirement from an external device coupled to the second connector, in response to a determination to receive DC power; send at least some of the DC power received from the third connector to the energy storage device at a second time; and send at least some of the DC power received from the third connector to the second connector at a third time.

Embodiment A23. The apparatus of any of embodiments A1 through A22, the charging circuitry comprising a processor programmed to: determine how to utilize the DC power received from the first connector based on at least one of a state of the energy storage device or a power requirement from an external device coupled to the second connector; send a first portion of the DC power received from the first connector to the energy storage device; and send a remaining portion of the DC power received from the first connector to the second connector.

Embodiment A24. The apparatus of embodiment A23, the processor further programmed to simultaneously send power from both the energy storage device and the first connector to the second connector. Embodiment A25. The apparatus of any of embodiments A1 through A24, the charging circuitry configured to: detect that power is no longer supplied being supplied through the first connector; and send DC power from the energy storage device through the first connector in response to said detection.

Embodiment A26. The apparatus of any of embodiments A1 through A25, the charging circuitry configured to: receive an alert through the first connector; and send DC power from the energy storage device through the first connector in response to the alert.

Embodiment A27. A method of distributing power, the method comprising: receiving direct-current (DC) power at a first connector of an edge device mounted in a wall of a building at a first power level; storing at least some of the power received at the first power level in an energy storage device; and providing at least some of the power received to an external device through a second connector of the edge device as load power.

Embodiment A28. The method of embodiment A27, further comprising converting at least some of the DC power received into alternating-current (AC) power and providing the AC power to the external device through the second connector.

Embodiment A29. The method of embodiment A27 or A28, further comprising: detecting that the power is no longer being received at the first connector; and sending power from the energy storage device through the first connector in response to said detecting.

Embodiment A30. The method of embodiment A29, wherein the power received at the first connector includes first power delivered over a first set of conductors of the first connector, and second power delivered over a second set of conductors of the first connector; the first power is stored in the energy storage device; and the second power is provided to through the second connector as load power.

Embodiment A31. The method of embodiment A30, wherein the first power is negotiated and received in a way that is compliant with an IEEE power over Ethernet standard.

Embodiment A32. The method of any of embodiments A27 through A31, further comprising: receiving a user input; sending a wireless signal from the edge device to a module holding the energy storage device; providing an alert to the user from the module in response to the wireless signal; wherein the module is positioned in the edge device at a first time when the at least some power received from at the first connector is stored in the energy storage device, and the module is removed from the edge device at the time the user input is received. Embodiment A33. The method of any of embodiments A27 through A32, further comprising: communicating with at least one other edge device; and routing power between the energy storage device and the at least one other edge device based on the communication.

Embodiment A34. The method of embodiment A33, further wherein the routing power is also based on at least one of a state of the energy storage device or a power requirement from an external device coupled to the second connector.

Embodiment A35. The method of any of embodiments A27 through A34, wherein the at least some of the power provided to the external device is routed from the first connector to the second connector without being stored in the energy storage device.

Embodiment A36. The method of any of embodiments A27 through A35, wherein a percentage of power received at the first power level received stored in the energy storage device is dependent upon a power requirement of the external device.

Embodiment A37. The method of any of embodiments A27 through A36, wherein said storing of at least some of the power received at the first power level in the energy storage device occurs and said providing of at least some of the power received to the external device through the second connector of the edge device as the load power both occur simultaneously.

Embodiment A38. The method of any of embodiments A27 through A37, wherein the storing of at least some of the power received at the first connector in the energy storage device occurs over a first time period, the method further comprising: providing substantially the first level of power received at the first connector during a second time period as load power; and providing at least some of the power stored in the energy storage device during the first time period as load power during the second time period; wherein the load power is provided at a second power level, greater than the first power level, during the second time period.

Embodiment A39. The method of embodiment A38, wherein no power received at the first connector during the second time period is stored in the energy storage device.

Embodiment A40. At least one machine readable medium comprising one or more instructions that in response to being executed on a computing device cause the computing device to carry out a method according to any one of embodiments A27 to A39.

Embodiment A41. A power distribution system comprising: a direct-current (DC) distribution unit; a cable having a first end coupled to the DC distribution unit; an energy storage device; and an edge device comprising: a mechanical structure configured to mount the edge device into a wall of a building; a second connector, coupled to the energy storage device, and positioned to be exposed while the edge device is mounted into the wall; a first connector, coupled to a second end of the cable, and positioned to be hidden within the wall while the edge device is mounted into the wall; and circuitry, coupled to the first connector and the energy storage device, to provide energy received from the second connector to the energy storage device.

Embodiment A42. The system of embodiment A41, wherein the DC distribution unit is compliant with an IEEE power over Ethernet standard as power sourcing equipment.

Embodiment A43. The system of embodiment A41 or A42, wherein the cable comprises only eight conductors, each smaller than 18 AWG.

Embodiment A44. The system of any of embodiments A41 through A43, wherein the edge device includes the energy storage device and the mechanical structure is further configured to hold the energy storage device.

Embodiment A45. The system of any of embodiments A41 through A44, a second energy storage device coupled to the edge device.

Embodiment A46. The system of any of embodiments A41 through A45, wherein the cable is a first cable, the energy storage device is a first energy storage device, and the edge device is a first edge storage device, the system further comprising: a second edge device including the second energy storage device; and a second cable having a first end coupled to the first edge device and a second end coupled to the second edge device; wherein the first edge device includes the first energy storage device and the second edge device includes the second energy storage device.

Embodiment A47. The system of embodiment A46, wherein the first cable and the second cable each comprise only eight conductors, each smaller than 18 AWG.

Embodiment A48. The system of embodiment A46 or A47, the circuitry of the first edge device comprising: a network interface coupled to second cable; a processor coupled to the network interface and programmed to: communicate through the network interface with a processor of the second edge device to determine whether to send or receive DC power through the second cable; send DC power from the energy storage device through the second cable at a first time in response to a determination to send DC power; determine how to utilize the DC power received from the second cable based on at least one of a state of the first energy storage device or a power requirement from an external device coupled to the second connector, in response to a determination to receive DC power; send at least some of the DC power received from the second edge device through the second cable to the first energy storage device at a second time; and send at least some of the DC power received from the second edge device through the second cable to the second connector at a third time.

Remote Dimming of Lighting

Embodiments are described herein that allow an Ethernet switch, router, or other equipment, to be configured to be compliant with IEEE power-over-Ethemet (PoE) standards such as 802.3af, 802.3at, and 802.3bt as power sourcing equipment (PSE) but provide an additional capability to power and control LED lighting loads by directly providing the power for the LEDs. This means that the module connecting to the PoE cable may not include power conversion and/or complicated control circuitry and may be able to directly provide the power from the PoE cable to the LEDs themselves. In some embodiments, the LED lighting load may not include a data connection to the Ethernet network, so that all of the intelligence to expose the LED light to the network and respond to network control of the LED light is handled in the PSE. This may allow for a much lower-cost device than solutions utilizing a traditional networked LED driver as is common in commercial installations today.

Embodiments may be included into a traditional PoE PSE Ethernet switch and may support IEEE standards-compliant PDs in addition to PDs consistent with the disclosures herein, but other embodiments may not support IEEE compliant PoE PDs. In some embodiments, the device driving the PoE cables may not include Ethernet switching capability at all, but may simply expose the lighting devices to the network as a network end-point and control the lighting devices by the amount of power provided to the cables connecting the lighting device to the PSE.

Ethernet switches or other devices acting as PSE should be compliant with appropriate IEEE standards, such as 802.3af, 802.3at, and 802.3bt, to determine how much power can be provided and whether to provide that power on 2 pairs of wires of the Ethernet cable or on all 4 pairs of wires. While the appropriate IEEE standards should be consulted for a full description of how the power negotiation is performed, a quick overview is presented here. An IEEE compliant PSE initially detects whether or not the PD has a signature resistance between PoE power pins of 19-26.5 kQ (using a voltage of 2.7V-10.1V). If the PD has a valid signature resistance, the PSE applies a classification voltage of 14.5V-20.5V and detects the current drawn by the PD to determine a power class for the PD. In addition, communication over the Ethernet connection at the link layer using LLDP may be used for higher power classes defined by IEEE 802.3bt. As of the time of this filing, 8 power classes are defined for PoE PDs by IEEE specifications. The inventor realized that by providing a different signature resistance, it would be possible to have a PD that did not indicate IEEE compliance and yet provide other mechanisms for the PD to provide its characteristics to the PSE. This allows the PSE to provide specialized support for the PD while still (optionally) being fully compliant with IEEE standards for PoE. As one example, the PSE may determine that the PD is an LED load and provide a constant current (CC) or constant voltage (CV) drive signal for the LED(s) over the Ethernet cable and also may modulate that signal using PWM, PDM, or analog modulation to control the brightness of the LED(s). While it might be possible to provide similar information using LLDP or other data communication over Ethernet between the PD and the PSE, that may add significant complexity and cost over other embodiments disclosed herein.

In some embodiments, the PSE may utilize a standard PSE integrated circuit with additional logic to manage the non-standard devices, but in other embodiments, both standards- compliant PoE and specialized PoE can be implemented using a standard microcontroller (MCU) or other processor. By adding a proprietary extension to an IEEE 802.3 compliant PoE switch it may be possible to reuse the power limiting features of the PSE or dedicated MCU to dim individual LED loads directly from the switch. This eliminates the redundancy of having to receive PoE power decoupled from the LED driver circuit and performing DC-to-DC conversion in the PD and allows a "driverless" end point at a PD functioning as a luminaire, saving significant cost and yielding better efficiency. The PSE could still be a fully IEEE compliant and operate as a standard PoE switch or router when used with compliant PoE PD loads, but allow the extension to operate as CC LED dimmer for individual ports coupled to a custom LED load. As the PoE standard requires individual classification by port, a special PoE switch could offer a hybrid mode where some ports are connected to LED loads (or other custom PoE loads) and others to standard PoE compliant devices.

An embodiment of a PD consistent with this disclosure may include a detection resistor outside of the valid 19-26.5 kQ range specified by IEEE PoE standards to indicate that it is not standards compliant. Non-limiting examples of a detection resistor used by a PD consistent with this disclosure include, but are not limited to, lkQ, lOkQ, 50kQ, and lOOkQ. In some embodiments, no detection resistor is included, creating a high impedance across the power wires of the PoE Ethernet cable. As long as the non-compliant PD does not have a detection resistor of 19-26.5 kQ, the PD will not be presumed to be compliant with IEEE PoE standards.

An Ethernet cable used for PoE (e.g. a category 5, category 5e, category 6, or category 7 cable) contains 4 twisted pairs of wires that are typically 20-24 AWG. 10/100BASE-T Ethernet (10/100 Mb Ethernet) only utilizes 2 of the 4 twisted pairs for data communication, while 1000BASE-T (Gb Ethernet) uses all 4 pairs for data communication. Depending on the PoE power classification, two or four pairs may be used for power. Given the fact that 2 pairs are not used for 10/100BASE-T communication, and even for the auto-negotiation phase on a Gb port, the 2 unused pairs may be used as an alternative communication path for a proprietary PD, such as an LED-driver module. Other embodiments may use the same wire pairs as used for Ethernet communication, but using a different protocol. Any type of communication protocol may be used for the communication between the PD and the PSE consistent with this disclosure, such as, but not limited to, RS-232, RS-422, RS-485, basic universal asynchronous receiver-transmitter (UART) protocols, inter-integrated circuit (I2C), universal serial bus (USB), other full-duplex or half-duplex bidirectional serial protocols, unidirectional serial protocols, parallel communication protocols, combinations of pre-determined voltage levels on the wires of the cable, or any other type of communication between the PD and the PSE.

Depending on the embodiment, the PSE could determine that the detection resistor of the PD is outside of the 19-26.5 kQ range and then attempt to communicate with the PD using the pre-established non-standard communication protocol on the unused pairs, or first try to communicate with the PD using the pre-established non-standard communication protocol and then if no communication can be established, go through the IEEE PoE configuration procedure.

Any amount or type of information may be provided by the PD to the PSE using the non standard communication protocol, depending on the embodiment, but a PD acting as an LED driver may communicate a CV voltage level or CC current level to be used to drive the LED(s). The LED driver may also communicate other information, such as information about which wire pairs on the PoE cable are used, information about different LEDs coupled to different wire pairs, minimum and/or maximum allowable current and/or voltage levels, brightness vs voltage relationships (e.g. curves or tables), brightness vs current relationships, or any other information related to the PD or external device (e.g. LEDs or LED arrays) coupled to the PD. In some embodiments, a PD coupled to an LED array with different color LEDs coupled to different wire pairs, such as a luminaire with red LEDs coupled to a first wire pair, green LEDs coupled to a second wire pair, blue LEDs coupled to a third wire pair, and white LEDs coupled to a fourth wire pair, may provide information about the configuration to the PSE which can then control the color of the luminaire by the ratio of the currents provided on the different wire pairs. In another example, information indicating that cool white LEDs (e.g. 5000K) are coupled to two of the wire pairs and warm white LEDs (e.g. 2700K) are coupled to the other two wire pairs may be provided to the PSE which allows the PSE to control a color temperature of the white light from the luminaire.

Information to be provided by the PD can be programmed into the PD at the factory during manufacturing, after manufacturing but before installation, at installation, or even after installation, using any technique, including, but not limited to, programming a non-volatile memory and including that in the PD, installing one or more resistors with particular valuables representing various information, setting jumpers or switches on the PD, or having code in a processor of the PD that can query an attached LED array to determine information about the array. In some embodiments, a non-volatile memory of the PD may be programmed in-situ. This can be done using any technique, including, but not limited to, sending the information to be programmed into the non-volatile memory to the PD and having circuitry on the PD program the non-volatile information, using a test fixture to program the non-volatile memory on the PD, or using a radio-frequency identification (RFID) signal to program an RFID tag (e.g. a near field communication (NFC) tag or other type of RFID tag) which acts as the non-volatile memory on the PD.

After receipt of the information from the PD, the PSE may control the PD based on the information received. In addition, the PSE may expose the PD as a device on a network, which may be the Ethernet network switched by the PSE, based on the information received. In some embodiments, the PSE may expose an individual PD as a device on the network, but in other embodiments the PSE may aggregate multiple PDs into a single entity to be exposed on a network. If the network utilizes internet protocol (IP), an IP address may be allocated for each individual PD, an aggregate of PDs, or as functions within the PSE which may have its own IP address. Any discovery protocol may be used to expose the device and its capabilities to other devices on the network, including, but not limited to, IP -based discovery protocols such as universal plug-and-play (UPnP), simple service discovery protocol (SSDP - which uses UPnP protocols), multicast domain name service (mDNS), or AllJoyn (which utilizes mDNS). Any data structure, protocol, or technique can be used to specify the functionality and control parameters of the PD through the discovery service, including, but not limited to, DotDot from the Zigbee Alliance, lightweight machine-to-machine protocol (LWM2M) from the Open Mobile Alliance (OMA), specifications from the Open Connectivity Foundation (OCF), Mesh Objects, JavaScript Object Notation (JSON) objects, extensible Markup Language (XML) objects, other standards, data structures, or mechanisms, or combinations thereof. Once the existence and capabilities of the PD are exposed on the network, other applications, devices, or entities may control the PD through the PSE, but the exact mechanisms used to do that, which may be standards-based or proprietary, are beyond the scope of this disclosure, although examples might include the ability to turn the LEDs coupled to the PD on or off, set a brightness level of the LEDs, control a color or color temperature of the LEDs or query a status of the LEDs.

In some embodiments, the PSE may be coupled to an emergency power source, which may be centralized or distributed, and may control the lighting PDs as a part of an emergency lighting system. In some cases, some PDs may have their own battery and the PSE may be able to receive power from the battery of a PD and send it to another PD, either because it does not have a battery or because its battery has been depleted.

While configuring a lighting device as a PD is discussed at length herein, other types of devices may be coupled to a PSE as a PD in some embodiments, such as various sensors (e.g. temperature sensors, gas sensors, water sensors, contact sensors, or any other type of sensor), USB wall-plugs as disclosed in provisional patent application 62/822,329 filed on 3/22/2019 which is incorporated by reference herein, amplified speakers, information technology (IT) equipment, or any other type of device.

Reference now is made in detail to the examples illustrated in the accompanying drawings and discussed below.

FIG. 6 shows a block diagram of an embodiment of a power-over-Ethernet (PoE) system 600. The system 600 includes power sourcing equipment (PSE) 610 coupled to a computer network 601. The computer network 601 may be any type of computer network, but in some embodiments the computer network 601 may be an Ethernet network such as, but not limited to, a 10BASE-T, a 100BASE-T, or a 1000BASE-T network that utilizes a data cable with 4 pairs of wires. The data cable may be known as a category 3, a category 5, a category 5e, a category 6, or a category 7 cable in some embodiments. The data cable may utilize wires having any size but some embodiments, may use wire with 20-24 AWG and the data cable may be shielded or unshielded.

The PSE 610 includes one or more connectors 611-619 which may be used to couple to other devices 631-639 using data cables 621-629. The connectors 611-619 may be any type of connector, but in some embodiments, the connectors 611-619 are RJ-45 connectors as specified for 10/100/1000BASE-T networks. The PSE 610 may include Ethernet router, switch or hub functionality in some embodiments but in other embodiments, the PSE 610 may be a mid-point device which simply injects power on the data cables 621-629 without impacting the data communication. In at least one embodiment, the PSE 610 is an end point device which terminates the network 601 and simply provides power to other devices 631-639.

Devices 631-639 coupled to the PSE 610 may be a device 639 which does not use power from its data cable 629, a device which is a powered device (PD) 631 compliant with an IEEE PoE standard, or a powered device 632 which is non-compliant with an IEEE PoE standard. The devices 631-639 may implement any function and may connect to the Ethernet network provided from the PSE 610. In some embodiments, however, the PD 632 may not include circuitry to connect to the Ethernet network and may simple communicate with the PSE 610 over the data cable 622 using other communication protocols.

In some embodiments, the PD 632 may be coupled to one or more LEDs 642 or may include one or more LEDs 642. As the term is used herein, an LED may be a traditional light emitting diode, an organic light emitting diode, or any other type of solid-state device which emits light dependent upon an amount of current passing through it. In at least one embodiment, the PD 632 may include a circuit board that includes an RJ-45 socket (i.e. a female connector) to couple to data cable 622. The circuit board of PD 632 may include a non-volatile memory which may be an RFID tag that is programmed with information related to the LED 642, such as a CC drive current or a CV drive voltage.

FIG. 7 shows a more detailed block diagram of a portion of an embodiment of the system 600 including additional detail about PD 631 which is compliant with an IEEE PoE standard and PD 632 which is not compliant with an IEEE PoE standard, which means that it does not fully implement the negotiation defined in those standards for determining how much power the PD 632 is requesting. PSE 610 includes a connector 611 coupled to a data cable 621 which has 4 twisted pairs of wires. While other wiring schemes may be used in embodiments, one pair of wires of cable 621 is coupled to pins 1 and 2 of connector 611, a second pair of wires of cable 621 is coupled to pins 3 and 6 of connector 611, a third pair of wires of cable 621 is coupled to pins 4 and 5 of connector 611, and a fourth pair of wires of cable 621 is coupled to pins 7 and 8 of connector 611.

A 10/100BASE-T Ethernet network utilizes two pairs of wires on an Ethernet cable, the pair connected to pins 1 and 2 and the pair connected to pins 3 and 6. While the other pins (4, 5, 7, and 8) are used for data communication by 1000BASE-T networks (which use all 4 twisted pairs on the cable for data communication), 10/100BASE-T networks do not. The PD 631 includes an Ethernet device 711 that couples to the first pair of data communication wires through transformer 712 and the second pair of data communication wires through transformer 713. The Ethernet device 711 may implement any functionality, including, but not limited to, a wireless access point, a printer, another network switch/router, a camera, a voice-over-IP (VOIP) phone, an IP television (IPTV) set-top box (STB), or a networked LED driver.

IEEE PoE standards define mechanisms to send power over the data cable 621. Various configurations are defined, including sending power over the wire pairs unused by 10/100BASE- T (pins 4, 5, 7, and 8), power over the wire pairs used for data communication (pins 1, 2, 3, and 6), or all 4 pairs of wires on the data cable 621. The PD 631 includes additional circuitry to enable the PSE 610 to determine that the PD 631 is compliant with an IEEE PoE standard. The circuitry may include a signature resistor 716 that may have a nominal resistance of 25 kQ which is used to indicate to the PSE 610 that the PD 631 is compliant. In the embodiment shown, the circuitry also includes two full-wave rectifiers 714-715 which allow power on the first two pairs (1, 2, 3, 6), second two pairs (4, 5, 7, 8), or all four pairs to be received by the PD 631 and provided as a positive voltage 717 to power the PD 631, which may include the Ethernet device 711. In embodiments, the PD 631 may have additional circuitry to allow a particular class of power to be requested from the PSE 610 consistent with the IEEE PoE standards. In addition, the Ethernet device 711 may be able to communicate with the PSE 610 using LLDP to further specify power requirements to the PSE 610.

PD 632 is an embodiment of an LED driver device which is not compliant with IEEE PoE standards. PD 632 is coupled to the RJ-45 connector 612 of the PSE 610 using a standard Ethernet cable (e.g. category 3, 5, 5e, 6, or 7). Note that PD 632 in this embodiment does not include an Ethernet device and does not communicate using Ethernet protocols. PD 632 may be configured to accept power only on a particular set of wires of the cable 622, such as pins 5 and 8 in the example shown. Other PD devices may be able to accept power over any other combination of wires of the cable 622, including configurations of wires which are consistent with IEEE PoE standards as described above.

The PD 632 includes a mechanism to inform the PSE that it is not compliant with IEEE PoE standards but still is requesting power be provided using a mechanism that is not standards compliant. Any mechanism can be used for this, but some embodiments may include a signature resistor 726 that is outside of the 19 kQ - 26.5 1<W signature resistance used by IEEE PoE standards. Any resistance value outside of that range may be used in embodiments, including resistances less than 19 kQ, such as 15 kQ, or 10 kQ, and resistances above 26.5 kQ, such as 30 kQ, 50 1<W or 75 kW. In some embodiments a signature resistor 726 of about 100 kW may be used to signify that the PD 632 is requesting non-standard power delivery over the cable 622 consistent with this disclosure.

The PD 632 may also include circuitry 721 to communicate information about the PD 632 and/or an externally coupled device (e.g. LED 642) to the PSE 610. In some embodiments, the circuitry 721 may include a processor coupled to one or more wires of the cable 622 for communication with the PSE 610. In some embodiments, the circuitry 721 may be directly connected to the cable 622 through low-resistance conductors. In other embodiments, the circuitry 721 may be AC coupled to the wires of the cable 622 using capacitors 722, 723 or inductively coupled to the wires of the cable 622 using a transformer. The circuitry 721 may include jumpers, switches, or resistors that can be sensed to determine the information to send.

As a non-limiting example, a PD 632 may offer support for a variety of different LED 642 loads, including 8 different predefined CC currents and 8 different predefined CV voltages which can be encoded by a 4 position dipswitch or as a jumper to indicate CC vs CV and a single resistor with one of 4 different resistance values that can be measured by the circuitry 721. In some embodiments, the jumpers, switches, and/or resistances may be determined by the PSE 610 over the cable 622 with minimal to no active circuitry 721 in the PD 632. In another embodiment, the circuitry 721 includes a non-volatile memory holding previously stored information which is then sent to the PSE 610. In at least one embodiment, the non-volatile memory is implemented as an RFID tag that has had the information stored into it by an RFID programmer using radio- frequency communication. A processor or other circuit within the circuitry 721 can read the information from the RFID tag and send it to the PSE 610 or in some embodiments, the RFID tag may be coupled to the cable 622 to allow the PSE 610 to directly read its contents.

The PD 632 may also include power circuitry to accept power provided by the PSE 610 over the cable 622. Depending on the embodiment, the circuitry may include diodes in various configurations, including the full-wave rectifier 724 shown, capacitors 725, voltage limiters, or other circuitry to generate one or more power supplies 727 within the PD 632. Note that in some embodiments, the rectifier 724 may be eliminated because the LEDs 642 naturally act as a rectifier. In embodiments, the circuitry 721 may be powered from one of the power supplies 727 generated from power supplied over the cable 622, although in other embodiments, the circuitry 721 may be powered by a battery or other power source inside or outside of the PD 632.

The circuitry 721 is configured to communicate with the PSE 610 and may use any protocol, standard or proprietary, for that communication, depending on the embodiment. In at least one embodiment, the circuitry 721 is low power circuity that can function from the power provided by the PSE during the resistance detection as the resistance of the signature resistor 726 is being determined. In such cases, the current draw of the circuitry 721 may be taken into account for the selection of the resistor to be used for the signature resistor 726. For example, if the target resistance of the signature resistor 726 is 100 1<W, and the circuitry 721 may consume 10 micro-amperes (mA) if the power supply 727 is at 5 V, a 125 kQ resistor may be selected so that 50 mA of current is drawn by the PD 632 at 5 V consistent with a 600 1<W signature resistance. Care should also be taken to assure that even under the full range of compliant test voltages defined by IEEE PoE standards (2.7V- 10. IV), the current drawn by PD 632 does not fall into the range of 69 kD - 26.5 1<W which indicates an IEEE compliant device.

Various embodiments may initiate the communication between the circuitry 721 of the PD 632 and the PSE 610 using various techniques. In some embodiments, the circuitry 721 may simply start sending the information as soon as it receives adequate power and the circuitry 721 may send it a predetermined number of times, such as once, twice, or 10 times, or may simply repeat sending it until a message is received telling the circuitry 721 to stop sending or power is lost. In other embodiments, the circuitry 721 may wait for a message from the PSE 610 before responding to the message with the information.

Any type of communication protocol may be used for the communication between the circuitry 721 and the PSE 610, including, but not limited to, standard communication protocols such as USB, RS-232, RS-485, 12C, serial peripheral interface (SPI), Microwire, or 1-Wire, or non-standard serial or parallel interfaces such as a simple UART serial protocol or a multi -bit data bus with a 2 or 3 wire handshake.

In some embodiments, the circuitry 721 may control a switch 728 to enable a power supply 727 to provide power 729 to the load, such as LED 642. The switch 728 may include one or more of a field-effect transistor (FET), a silicon-controlled rectifier (SCR), a triode for alternating current (triac), a relay, or other component. In some embodiments, the circuitry 721 may operate at a lower voltage than a minimum activation voltage for the LED 642, so no switch 728 is used, although a separate voltage regulator or other voltage protection may be used for circuitry 721 to protect it from higher voltages that may be used to drive the LED 642 during operation.

FIG. 8 shows a more detailed block diagram of one port of an embodiment of power system equipment (PSE) 610 of the PoE system 600. The PSE 610 may include any number of ports which may be implemented independently or may share one or more of the components shown in FIG. 8. The PSE 610 has a connection to a network 601, which may be an Ethernet network in some embodiments, and has a connector 611 for the port shown, which may be an 8 contact RJ-45 socket in some embodiments. In some embodiments, the PSE 610 includes an Ethernet switch or router component 820 which can implement layer 2 or higher

switching/routing functionality of the Ethernet network and may connect to any number of Ethernet ports. One port of the Ethernet component 820 is coupled to two pairs of contacts of the connector 611 using transformers 812, 813 compliant with 10/100BASE-T specifications.

The PSE 610 also includes PoE circuitry 830. While a connection to the two pairs of contacts of connector 611 that are not used for data is shown, other embodiments may connect to any number and any combination of contacts of the connector 611. The PoE circuitry 830 may include standards-compliant circuitry 832 which manages PoE in a way that is compliant with IEEE PoE standards. This may include the detection of a signature resistance and a

determination of a class of power, among other requirements of the standards.

The PoE circuitry 830 also includes circuitry 833 to provide power to a PD that is not standards-compliant through the connector 611. In some embodiments, the circuitry 833 may be merged with circuitry 832 to serve both standards-compliant and non-compliant PDs. The circuitry 833 detects that the PD coupled to the connector 611 is not standards compliant yet is requesting power be provided over its cable. This may be done by any method but in some embodiments, it may be determined by providing a voltage across a pair of pins of the connector and detecting a particular range of current (i.e. detecting a signature resistance). In other embodiments, the circuitry 833 may simply listen for a message from the PD or may send a request for information to the PD using a simple communications protocol.

The circuitry 833 may also receive information about the PD through the connector 611. This information may include information about how to power the PD such as a CC drive current, a CV drive voltage, a maximum power draw, a duty-cycle requirement, a configuration of the PD or a load coupled to the PD, or any other information related to the PD or a load coupled to the PD, such as one or more LEDs coupled to the PD.

The PoE circuitry 830 may expose the existence of the PD to the network 601. This may be done through a port of the Ethernet component 820 and may utilize any protocol to advertise the existence of the PD and any capabilities of the PD based on the information received. The PoE circuitry may also receive commands from the network 601 to control the PD and use the circuitry 833 to send a power signal through the connector 611 to the PD based on the commands received through the network 601 and the information received from the PD. FIG. 9 shows waveforms of PoE negotiation for an IEEE compliant PD including a voltage waveform 900 and a current waveform 950. While the appropriate IEEE standards, such as IEEE 802.3af, IEEE 802.3at, and/or IEEE 802.3bt, should be consulted for a full description of how the negotiation is performed, a quick overview is presented here. An IEEE compliant PSE initially detects whether or not the PD has a signature resistance between PoE power pins of 19-26.5 kQ. This is done by presenting a test voltage 902 of 2.7V-10. IV to the PD and detecting the current 952. If the PD has a valid signature resistance, the PSE applies a classification voltage 904 of 14.5V-20.5V and detects the current drawn by the PD 954 to determine a power class for the PD. Once the appropriate power class has been determined, the PSE may apply a voltage 908 of 44V-57V to the appropriate pins of the Ethernet cable to provide the requested amount of power to the PD. The current 958 may be limited by the power class negotiated.

FIG. 10 shows waveforms of PoE negotiations for an embodiment of a PD that is consistent with IEEE standards, but provides additional capability, which may be referred to as being non-compliant with the IEEE standards. FIG. 10 shows voltage waveforms 1000, current waveforms 1050, and data waveforms 1090. Depending on the embodiment, the data

communication 1090 may take place on the same wires as the voltage waveform 1000 and current waveform 1050 or may utilize different wires on the same cable. In the embodiment shown, the PSE starts by applying a test voltage 1002 to the Ethernet cable in a manner consistent with IEEE standards for determination of the signature resistance. The current 1052 is then detected to determine the signature resistance by dividing the voltage by the current. If the PD were a standards-compliant PD, the PSE might continue as shown in FIG. 4, but if the signature resistance is outside of the valid standards-compliant range, and in a range

predetermined to invoke the non-standard PoE described here, communication between the PSE and the PD may commence.

The communication between the PSE and PD may vary depending on the embodiment, but in the embodiment shown, the PSE waits for a period of time after providing the test voltage 1002 to allow the PD to receive power and wake up, then sends a request 1092 to ask the PD to send information about the PD and/or its associated load to the PSE. The PD sends the information 1094 to the PSE which may respond with an acknowledgement 1096. In some embodiments, the acknowledgement may include configuration information such as information to turn on a switch to drive the attached load or other configuration information, although other embodiments may not utilize an acknowledgement 1096. The PSE may expose information related to the PD to a network and may receive commands for the PD, such as a command to turn on the luminaire represented by the PD to full brightness. The PSE may then provide a power signal represented by voltage waveform 1004 to the PD over the Ethernet cable. Note that in the embodiment shown, the LED load does not turn on until the applied voltage 1004 nears its peak value. Once the LED load turns on, the PSE may provide a full-on current level 1054 as determined by the information that was received by the PSE. The PSE may receive a command to set the luminaire brightness to a 50% level at a later time. The PSE may then respond to this by setting the current level 1056 to 50% of maximum. Note that the voltage may change very little when the current is cut in half due to the non-linear voltage behavior of an LED. The PSE may then receive a command to turn off the LED, causing it to set the current 1058 to zero.

FIG. 11 is a flowchart 1100 of an embodiment of negotiating a power request for an LED driver in a PoE system. The method of the flowchart 1100 may be used in a device which may also provide Ethernet switching or routing, may be compliant with an IEEE PoE standard, and/or may act as a standalone device to provide power over data cables to one or more devices.

The flowchart 1100 begins by providing a detection voltage 1103 on a cable to another device, which may be referred to as a powered device (PD) herein. The PD may be compliant with an IEEE PoE specification or it may be consistent with the disclosures herein. The PD can implement any type of functionality, but it may include one or more LEDs or may be coupled to one or more LEDs in some embodiments. The detection voltage can be any voltage level, but in at least some embodiments, the detection voltage may be between about 2.8 V and about 10 V.

In at least one embodiment, a 5 V detection voltage may be used.

Once the detection voltage has been provided 1103, a current provided to the PD may be measured 1105. Based on the measured current, a signature resistance may be calculated for the PD. The value of the signature resistance may be useful in determining whether the PD is compliant with and IEEE PoE standard, compliant with the present disclosure, or whether the PD is not configured to accept power over the data cable. In some embodiments, the signature resistance is checked 1110 to see if the PD is compliant with an IEEE PoE standard, which defines a nominal resistance of 25 kQ to indicate compliance with the IEEE PoE standard. In some embodiments, if the signature resistance is found to be in a range the includes 25 kQ, such as between 19 kQ and 26.5 1<W, the PD is determined to be compliant with an IEEE PoE standard and a PoE negotiation as defined by the appropriate IEEE PoE standard (e.g. 802.3af, 802.3at, or 802.3bt) may be performed 1113 to determine the appropriate power to apply to the cable. In embodiments, additional checks may be performed to determine 1120 if the PD may be able to receive power as defined herein. These checks may take any form, depending on the embodiment, including, but not limited to, a signature resistance outside of the range specified by IEEE PoE standards, a pattern of pull-up and/or pull-down resistors on the wires of the cable, a pattern of connections between wires of the cable, receiving data sent from the PD, or receiving a signal with a particular frequency and/or duty cycle from the PD. If it is determined 1120 that the PD is unable to receive power as disclosed herein, then no PoE is provided 1130 to the PD.

In at least one embodiment, a signature resistance of nominally 100 kQ (which may have a tolerance depending on the embodiment) may be used to indicate that a PD is capable of receiving power as described herein. So if it is determined 1120 that the signature resistance is about 100 kQ, communication 1123 with the PD may occur to receive information from the PD. The information received from the PD can be any type of information related to the PD, but in at least one embodiment, the PD may be a luminaire and information about how to drive the luminaire, such as a constant voltage drive level, a constant current drive level, or any other type of information about the luminaire may be provided to the PD. Any communication protocol used for the communication with the PD, standards-based or proprietary, and may take place over the cable coupled to the PD. The data communicated can be formatted in any way, but in some embodiments, the data may be formatted as a JSON object, XML code, binary data, or human-readable text-based descriptions.

Once the information about the PD (which may be an LED device in some embodiments) has been received, the existence of the PD may be exposed 1125 on a computer network. The PD may, in some embodiments, be exposed using a standard discovery protocol to allow it to be discovered and controlled by a variety of other devices. In other embodiments, the PD may be exposed to a proprietary application to allow that application to control the PD.

After the PD (which may be an LED driver in some embodiments) has been exposed, commands to control the PD may be received 1127. In response to receiving the commands, the PD may be controlled 1129 based on the received commands. In some cases, the received command may indicate a brightness level for an LED driver functioning as the PD. In some embodiments where the PD is an LED driver, the information received 1123 may indicate that the LED driver utilizes a constant-current (CC) drive. In response, the PSE may calculate an appropriate amount of current for the brightness based on a maximum current level for the LED driver or a brightness vs current relationship for the LED driver, and the calculated amount of current may be provided through the cable to the PD to set the desired brightness of the LED(s). The amount of current may be based on a brightness level indicated by the received command along with information indicating a full-brightness current level for the LED(s) received from the PD. So as a non-limiting example, if information indicating the a current of 1 A would provide full brightness, and a command indicating that the LED(s) should be turned on at 50%

brightness, a 500 mA signal may be provided to the LED driver though the cable. In some embodiments, the amount of current may be found using brightness vs current information which may be in the form of an equation (linear, polynomial, or other) or a table of values (which may have a complete set current values for each possible brightness level or current values for only some brightness levels which can then be interpolated).

In other embodiments where the PD is an LED driver, the information received 1123 may indicate that the LED driver utilizes a constant-voltage (CV) drive and/or may indicate a voltage level to use. In response, the PSE may calculate a percentage of on time to use to provide the desired brightness level for the LED(s). In some cases a linear relationship between a brightness level as a percentage of full brightness and the on time percentage may be used but in other cases, a non-linear relationship may be used which may be pre-determined by the PSE or may be based on information received from the LED driver. The PSE may then use the percentage of on time to generate the power signal using pulse-width modulation or pulse-density modulation and provide the power signal to the LED driver over the cable. As a non-limiting example, the LED driver may indicate that it is a CV driver and expects a 48V DC drive level. If a command is received indicating that the LED(s) should be turned on at a 50% brightness, a power signal with an amplitude of 48V and a 50% duty cycle at a given frequency, such as 120 Hz, may be provided to the LED driver through the cable.

Over time additional commands may be received 1127 and the PD controlled 1129 based on the received commands and the information received from the PD.

Examples of various embodiments Remote Dimming of Lighting are described in the following paragraphs:

Embodiment Bl. A method of providing power to a device over a cable, the method comprising: determining whether the device is able to receive power over the cable as specified by an open industry standard; in response to determining that the device is able to receive power over the cable as specified by the open industry standard, providing power to the device over the cable as specified by the open industry standard; in response to determining that the device is not able to receive power over the cable as specified by the open industry standard: receiving information from the device over the cable; exposing an existence of the device over a computer network; receiving a command for the device over the computer network; and providing a power signal over the cable to the device based on the command and the received information.

Embodiment B2. The method of embodiment Bl, wherein the open industry standard is a standard published by an IEEE 802.3 committee.

Embodiment B3. The method of embodiment B2, wherein the cable is compliant with power over Ethernet (PoE) cable requirements in a standard published by the IEEE 802.3 committee.

Embodiment B4. The method of embodiment B3, said receiving the information from the device over the cable comprising: receiving data on wires of the cable that are not specified for use by 10/100BASE-T communication on the cable.

Embodiment B5. The method of embodiment B3 or B4, said determining whether the device is able to receive power over the cable as specified by the open industry standard comprising: attempting to communicate with the device using a protocol other than an Ethernet protocol over wires of the cable that are not specified for use by 10/100BASE-T communication on the cable; and in response to successful communication with the device using the protocol other than the Ethernet protocol over the wires of the cable that are not specified for use by 10/100BASE-T communication on the cable, determining that the device is not able to receive the power over the cable as specified by the open industry standard.

Embodiment B6. The method of embodiment B5, wherein the information is received during the successful communication with the device using the protocol other than the Ethernet protocol over the wires of the cable that are not specified for use by 10/100BASE-T communication on the cable.

Embodiment B7. The method of any of embodiments B3-B5, said determining whether the device is able to receive power over the cable as specified by the open industry standard comprising: attempting to communicate with the device using a protocol other than an Ethernet protocol over wires of the cable that are not specified for use by 10/100BASE-T communication on the cable; in response to an inability to communicate with the device using the protocol other than the Ethernet protocol over the wires of the cable that are not specified for use by 10/100BASE-T communication on the cable: detecting a signature resistance of the device through the cable; and determining that the signature resistance is in a first range to indicate that the device is able to receive the power over the cable as specified by the open industry standard. Embodiment B8. The method of embodiment Bl, said determining whether the device is able to receive power over the cable as specified by the open industry standard comprising: detecting a signature resistance of the device through the cable; and determining that the signature resistance is in a first range to indicate that the device is able to receive the power over the cable as specified by the open industry standard.

Embodiment B9. The method of embodiment Bl or B8, said determining whether the device is able to receive power over the cable as specified by the open industry standard comprising: detecting a signature resistance of the device through the cable; and determining that the signature resistance is in a second range to indicate that the device is not able to receive the power over the cable as specified by the open industry standard and is able to provide additional the information about the device’s ability to receive the power signal over the cable.

Embodiment B10. The method of embodiment Bl, B8 or B9, said receiving the information from the device over the cable comprising: measuring two or more resistances between wires of the cable; and determining the information based on the two or more resistances.

Embodiment B 11. The method of any of embodiments B 1-B 10, further comprising: obtaining a brightness level for a lighting element of the device from the command; determining a drive characteristic for the lighting element based on the information; and generating the power signal based on both the brightness level and the drive characteristic.

Embodiment B 12. The method of embodiment Bl 1, the device comprising an LED driver.

Embodiment B 13. The method of embodiment Bl 1 or B12, further comprising:

calculating a percentage of on time of the power signal based on the brightness and the drive characteristic indicating that the lighting element utilizes a constant voltage drive signal; and using the percentage of on time to generate the power signal using pulse-width modulation or pulse-density modulation.

Embodiment B 14. The method of any of embodiments B 11-B 13, further comprising: calculating a current level for the power signal is on based on the brightness and the drive characteristic indicating that the lighting element utilizes a constant current drive signal; and generating the power signal with the calculated current level.

Embodiment B 15. The method of any of embodiments Bl 1-B13, further comprising: calculating a current level for the power signal is on based on the brightness and the drive characteristic indicating a brightness vs current relationship for the lighting element; and generating the power signal with the calculated current level.

Embodiment B 16. A method of driving a lighting load, the method comprising:

receiving a drive characteristic for the lighting load over a cable coupled to the lighting load; receiving a brightness level for the lighting load over a computer network; generating a power signal based on both the brightness level and the drive characteristic; and providing the power signal to the lighting load over the cable.

Embodiment B 17. The method of embodiment B 16, further comprising: calculating a percentage of on time of the power signal based on the brightness and the drive characteristic indicating that the lighting load utilizes a constant voltage drive signal; and using the percentage of on time to generate the power signal using pulse-width modulation or pulse-density modulation.

Embodiment B 18. The method of embodiment B 16, further comprising: calculating a current level for the power signal is on based on the brightness and the drive characteristic indicating that the lighting load utilizes a constant current drive signal; and generating the power signal with the calculated current level.

Embodiment B 19. The method of embodiment B 16, further comprising: calculating a current level for the power signal is on based on the brightness and the drive characteristic indicating a brightness vs current relationship for the lighting element; and generating the power signal with the calculated current level.

Embodiment B20. The method of any of embodiments B 16-B 19, further comprising: receiving information related to standards compliance from the lighting load over the cable; and determining whether to provide the power signal to the lighting load over the cable in response to the received information.

Embodiment B21. The method of any of embodiments B 16-B20, wherein the cable is compliant with power over Ethernet (PoE) cable requirements in a standard published by an IEEE 802.3 committee.

Embodiment B22. The method of embodiment B21, said receiving the drive characteristic comprising: receiving data on wires of the cable that are not specified for use by 10/100BASE-T communication on the cable using a protocol other than an Ethernet protocol.

Embodiment B23. The method of any of embodiments B16-B22, said receiving the drive characteristic comprising: measuring two or more resistances between wires of the cable; and determining the drive characteristic based on the two or more resistances. Embodiment B24. The method of any of embodiments B16-B23, the lighting load comprising an LED driver.

Embodiment B25. A method of driving a lighting load, the method comprising:

providing information based on a drive characteristic of the lighting load over a cable; providing a power signal from the cable; and providing the power signal to the lighting load.

Embodiment B26. The method of embodiment B25, wherein the cable is compliant with power over Ethernet (PoE) cable requirements in a standard published by an IEEE 802.3 committee.

Embodiment B27. The method of embodiment B26, said providing the information comprising: sending data on wires of the cable that are not specified for use by 10/100BASE-T communication on the cable using a protocol other than an Ethernet protocol.

Embodiment B28. The method of embodiment B26 or B27, further comprising providing a signature resistance in a predetermined range outside of a range of 19 kQ -26.5 1<W as measured through the cable as specified for PoE in the standard published by the IEEE 802.3 committee.

Embodiment B29. The method of embodiment B25, further comprising coupling one or more switches of resistors to the cable based to provide the information.

Embodiment B30. The method of any of embodiments B25-B29, further comprising: receiving the information through a radio-frequency communication at a first time; storing the information in a radio-frequency identification (RFID) chip; reading the information from the RFID chip through a wired interface at a second time later than the first time; and sending the information as data on the cable to provide the information over the cable.

Embodiment B31. The method of any of embodiments B25-B30, the lighting load comprising an LED driver.

Embodiment B32. At least one non-transitory machine readable medium comprising one or more instructions that in response to being executed on a computing device cause the computing device to carry out a method according to any one of embodiments B 1 to embodiment B31.

Embodiment B33. An apparatus for controlling brightness of a luminaire, the apparatus comprising: a first connector to couple to a drive cable for the luminaire; an interface to a computer network; power circuitry, coupled to the first connector, to generate a power signal at the first connector; a processor, coupled to the interface to the computer network and the power circuitry; a memory, coupled to the processor and storing instructions which, as executed by the processor, cause the processor to perform a method comprising: receiving a drive characteristic for the luminaire over a cable coupled to the luminaire; receiving a brightness level for the luminaire over a computer network; generating a power signal based on both the brightness level and the drive characteristic; and providing the power signal to the luminaire over the cable.

Embodiment B34. The apparatus of embodiment B33, the method further comprising: calculating a percentage of on time of the power signal based on the brightness and the drive characteristic indicating that a lighting element of the luminaire utilizes a constant voltage drive signal; and using the percentage of on time to generate the power signal using pulse-width modulation or pulse-density modulation.

Embodiment B35. The apparatus of embodiment B33, the method further comprising: calculating a current level for the power signal is on based on the brightness and the drive characteristic indicating that a lighting element of the luminaire utilizes a constant current drive signal; and generating the power signal with the calculated current level.

Embodiment B36. The apparatus of embodiment B33, the method further comprising: calculating a current level for the power signal is on based on the brightness and the drive characteristic indicating a brightness vs current relationship for the lighting element; and generating the power signal with the calculated current level.

Embodiment B37. The apparatus of any of embodiments B33-B36, the method further comprising: receiving information related to standards compliance from the luminaire over the cable; and determining whether to provide the power signal to the luminaire over the cable in response to the received information.

Embodiment B38. The apparatus of any of embodiments B33-B37, wherein the cable is compliant with power over Ethernet (PoE) cable requirements in a standard published by an IEEE 802.3 committee.

Embodiment B39. The apparatus of embodiment B38, said receiving the drive characteristic comprising: receiving data on wires of the cable that are not specified for use by 10/100BASE-T communication on the cable using a protocol other than an Ethernet protocol.

Embodiment B40. The apparatus of any of embodiments B33-B39, said receiving the drive characteristic comprising: measuring two or more resistances between wires of the cable; and determining the drive characteristic based on the two or more resistances.

Embodiment B41. The apparatus of any of embodiments B33-B40, the luminaire comprising an LED driver. Embodiment B42. An apparatus for providing power to a device over a cable, the apparatus comprising: a first connector to couple to the cable for the device; an interface to a computer network; power circuitry, coupled to the first connector, to generate a power signal at the first connector; and a processor, coupled to the interface to the computer network and the power circuitry, the processor programmed to determine whether the device is able to receive power over the cable as specified by the open industry standard; in response to determining that the device is able to receive power over the cable as specified by the open industry standard, the processor is further programmed to provide power to the device over the cable as specified by the open industry standard; in response to determining that the device is not able to receive power over the cable as specified by the open industry standard, the processor is further programmed to: receive information from the device over the cable; expose an existence of the device over a computer network; receive a command for the device over the computer network; and provide a power signal over the cable to the device based on the command and the received information.

Embodiment B43. The apparatus of embodiment B42, wherein the open industry standard is a standard published by an IEEE 802.3 committee.

Embodiment B44. The apparatus of embodiment B43, wherein the cable is compliant with power over Ethernet (PoE) cable requirements in a standard published by the IEEE 802.3 committee.

Embodiment B45. The apparatus of embodiment B44, the processor further programmed to receive data on wires of the cable that are not specified for use by 10/100BASE- T communication on the cable as at least a part of said receiving the information from the device over the cable comprising.

Embodiment B46. The apparatus of embodiment B44 or B45, the processor, as at least a part of said determining whether the device is able to receive power over the cable as specified by the open industry standard, further programmed to: attempt to communicate with the device using a protocol other than an Ethernet protocol over wires of the cable that are not specified for use by 10/100BASE-T communication on the cable; and in response to successful communication with the device using the protocol other than the Ethernet protocol over the wires of the cable that are not specified for use by 10/100BASE-T communication on the cable, determine that the device is not able to receive the power over the cable as specified by the open industry standard. Embodiment B47. The apparatus of embodiment B46, wherein the information is received during the successful communication with the device using the protocol other than the Ethernet protocol over the wires of the cable that are not specified for use by 10/100BASE-T communication on the cable.

Embodiment B48. The apparatus of any of embodiments B44-B46, the processor, as at least a part of said determining whether the device is able to receive power over the cable as specified by the open industry standard, further programmed to: attempt to communicate with the device using a protocol other than an Ethernet protocol over wires of the cable that are not specified for use by 10/100BASE-T communication on the cable; in response to an inability to communicate with the device using the protocol other than the Ethernet protocol over the wires of the cable that are not specified for use by 10/100BASE-T communication on the cable: detect a signature resistance of the device through the cable; and determine that the signature resistance is in a first range to indicate that the device is able to receive the power over the cable as specified by the open industry standard.

Embodiment B49. The apparatus of embodiment B42, the processor, as at least a part of said determining whether the device is able to receive power over the cable as specified by the open industry standard, further programmed to: detect a signature resistance of the device through the cable; and determine that the signature resistance is in a first range to indicate that the device is able to receive the power over the cable as specified by the open industry standard.

Embodiment B50. The apparatus of embodiment B42 or B49, the processor, as at least a part of said determining whether the device is able to receive power over the cable as specified by the open industry standard, further programmed to: detect a signature resistance of the device through the cable; and determine that the signature resistance is in a second range to indicate that the device is not able to receive the power over the cable as specified by the open industry standard and is able to provide additional the information about the device’s ability to receive the power signal over the cable.

Embodiment B51. The apparatus of embodiment B42, B49, or B50, the processor, as at least a part of said receiving the information from the device over the cable, further programmed to: measure two or more resistances between wires of the cable; and determine the information based on the two or more resistances.

Embodiment B52. The apparatus of any of embodiments B42-B51, the processor further programmed to: obtain a brightness level for a lighting element of the device from the command; determine a drive characteristic for the lighting element based on the information; and generate the power signal based on both the brightness level and the drive characteristic.

Embodiment B53. The apparatus of embodiment B52, the device comprising an LED driver,

Embodiment B54. The apparatus of embodiment B52 or B53, the processor further programmed to: calculate a percentage of on time of the power signal based on the brightness and the drive characteristic indicating that the lighting element utilizes a constant voltage drive signal; and use the percentage of on time to generate the power signal using pulse-width modulation or pulse-density modulation.

Embodiment B55. The apparatus of any of embodiments B52-B54, the processor further programmed to: calculate a current level for the power signal is on based on the brightness and the drive characteristic indicating that the lighting element utilizes a constant current drive signal; and generate the power signal with the calculated current level.

Embodiment B56. The apparatus of any of embodiments B52-B55, the processor further programmed to: calculate a current level for the power signal is on based on the brightness and the drive characteristic indicating a brightness vs current relationship for the lighting element; and generate the power signal with the calculated current level.

Embodiment B57. A light-emitting diode (LED) driver comprising: a first connector to couple to one or more LEDs; a second connector to couple to a cable; first circuitry to provide information about the one or more LEDs at the second connector; and second circuitry to send a power signal received at the second connector to the first connector.

Embodiment B58. The LED driver of embodiment B57, said second circuitry comprising two or more conductors respectively directly connecting two or more contacts on the first connector to two or more contacts on the second connector.

Embodiment B59. The LED driver of embodiment B57, said second circuitry comprising one or more of a full-wave rectifier or a switch configured to control whether the power signal is provide to the first connector.

Embodiment B60. The LED driver of any of embodiments B57-B59, said first circuitry configured to provide a signature resistance in a predetermined range outside of a range of 19 kQ - 26.5 1<W as measured through the second connector as specified by an IEEE power over Ethernet specification, wherein the second connector comprises an RJ-45 connector. Embodiment B61. The LED driver of any of embodiments B57-B60, said first circuitry comprising one or more switches or resistors configured based on the information to be provided.

Embodiment B62. The LED driver of any of embodiments B57-B61, said first circuitry comprising a writeable radio-frequency identification (RFID) chip configured to provide data stored therein through the second connector.

Embodiment B63. The LED driver of any of embodiments B57-B62, said first circuitry comprising a non-volatile memory configured to provide data stored therein through the second connector.

Constant-Current (CC) Dimming of Constant-Voltage (CV) Loads

Various types of LED loads may be configured to be driven by either a constant voltage (CV) driver or a constant current (CC) driver. Some LED loads may have both voltage level and current level specified so that either type of driver can be used. Some LED loads, such as LED strips or LED fl extape may be configured in the field so that while one drive parameter (e.g.. voltage for a LED strip specified for a CV driver) may stay the same as the configuration of the LED load changes, the other parameter (e.g. current for a CV load) may change. As a non limiting example, an LED lighting strip may be designed to be driven at 24 VDC and may be available at a variety of lengths up to 25 feet (ft), consuming 3.8 watts (W) per ft. Furthermore, the example LED lighting strip may be configured in the field to a shorter length at 2.4 inch (in) increments. Thus, the amount of current consumed by the example LED lighting strip driven at 24 VDC may vary from almost 4 amperes (A) for a 25 ft long strip consuming 95 W, to only 0.031 A for a 2.4 in long strip consuming less than 1 W, with a 10 ft long strip consuming 38 W which is 1.58 A at 24 VDC. So while a CV driver or power supply can be sold that will work with the strip cut to any length as long as it regulates the voltage to 24 VDC and can supply up to 95W of power, a different CC driver or power supply would be needed for each different length. Different LED strips are sold for different voltage level drivers. Some use 24 VDC as in the example above, but LED strips may commonly use 5 VDC, 12 VDC, or 48 VDC and strips for other voltages may also be available. Voltage regulated power supplies or CV LED drivers to drive those loads are also commonly available for those same voltages.

Note that as the terms are used here, constant current (CC) drive means that current is regulated and the voltage may vary as necessary to meet the desired current level. This may also be referred to as a current-regulated power supply. Constant voltage (CV) drive means that the voltage is regulated and the current is allowed to vary as necessary to keep the voltage at the desired level, which may also be referred to as a voltage-regulated power supply. A constant current drive may have its current level changed and a constant voltage drive may have its voltage level changed or rapidly switched on and off using pulse-width modulation (PWM) to provide dimming of the LED load.

Some CV drivers support dimming, although some do not. The dimming may be controlled by a 0-10V control signal, commands received over a network, infrared (IR) or radio- frequency (RF) commands from a remote control, or any other method. As was mentioned earlier, because LEDs exhibit highly non-linear behavior with respect to voltage, a CV driver uses PWM or PDM to vary the brightness of the LEDs. This may cause flickering or electromagnetic interference (EMI). Analog modulation of the current is generally thought to be a better solution for dimming LEDs, but this is not possible if the maximum current draw of the LED load is not known, which is the case for variable length LED strips as one non-limiting example.

Embodiments are disclosed here that allow analog modulation of the current for a CV load to provide smooth, flicker-free, low EMI, controlled dimming of CV loads such as variable length LED strips. Embodiments may automatically determine a maximum current for an attached LED load, and then perform analog modulation of that current to dim the LED load. The modulation may be linear in some embodiments, but other embodiments may use a current versus (vs) brightness curve (e.g. an equation or table lookup) or input from a sensor to determine how to modulate the current for a particular brightness level.

In some embodiments, a driver may be marketed for a particular voltage of CV LED load. Thus a first driver may be designed to support a 24 VDC CV load and a second driver may be designed to support a 12 VDC CV load. Some drivers may support a variety of CV loads set by a one or more switches, a particular value of resistor, a command received from a network or remote control before the load is powered, or any other mechanism. Other drivers may automatically determine a voltage for the CV load. In some embodiments, a driver may utilize a separate power supply that is selected to match the CV load and be able to operate over a range of voltages, such as 10 VDC to 30 VDC which would allow the driver to support both 12 VDC and 24 VDC CV loads when paired with a matching power supply.

In some embodiments, current metering may be provided at the output of the driver. The current metering may be included in an integrated circuit that is used to regulate the power output, a current-sensing coil or shunt resistor may be provided on the power output that can be monitored to determine the current flowing to the load. The driver may determine a maximum current (Imax) by providing the specified CV voltage to the load and measuring the current flowing to the load to determine the current flowing at maximum brightness of the load. This determination of Imax may be performed at any time, including, but not limited to, soon after power if first provided to the driver, in response to a command from a network or remote control, in response to actuation of a physical switch on the driver, or periodically. Once Imax has been determined, the driver can use that value to determine an amount of current to provide for a desired brightness level as a percentage of the maximum brightness, acting as a CC driver for the CV load. Embodiments may include voltage limiting circuitry to avoid damaging the load if the load changes after Imax has been determined.

If the load needs to be changed after an initial installation, such as cutting the LED strip or adding additional LED strip in series with the previously installed LED strip, an installer or electrician simply simply power off the driver, add or remove length to the CV LED load and power up the driver again. In embodiments, the driver may perform a new measurement to determine Imax after power cycle as discussed above.

In some embodiments, a driver may always act as a CC driver. In such embodiments, the driver may measure the output voltage as it ramps up the current provided to the load until the output voltage is equal to the specified CV drive level. Once the output voltage is equal to the CV drive level, the current can be measured to determine Imax. In some embodiments, the voltage may be measured near the load instead of at the driver. This may be useful in

embodiments where there is a significant length of wire between the driver and the load. Taking the concept further, embodiments may include an intermediate device between the driver and the load, which may be located close to the load, which can monitor the voltage level and

communicate with the driver to indicate that the proper CV voltage has been reached. This intermediate device may be referred to as a load identification device (LID). The LID could be set for a particular CV voltage to match the load, and a driver could be a universal driver able to support a LID for any CV voltage and power level within a maximum voltage and power capability of the driver.

As a non-limiting example, a CC driver could support universal voltage and drive current and reside away from the load as a stand-alone driver device. Such a universal driver (UD) may be a centralized driver capable of powering multiple loads and may utilize Ethernet cables with PoE to connect to LIDs. The UD could by default output a minimal voltage enough to power a remote LID, and once powered, the LID may indicate to the UD information about the load, such as whether the load is a CC or CV load and what voltage level or current level is requested by the load. The information may be provided to the UD over one or more wires of the cable coupling the LID to the UD. Some embodiments may be compatible described above in the Remote Dimming of Lighting secion, with the UD being power sourcing equipment (PSE) and the LID being a powered device (PD). Other embodiments of a LID may be passive and may use different resistance values between a designated pair of wires to indicate a particular CV or CC drive level.

If the LID indicates that the load is a CC load, the UD can adjust its settings to the max current indicated by the LID. If the LID indicates that the load is a CV load, the UD could start increasing its current output until the LID indicates the target voltage is achieved. As an example, the target voltage may be 24V but 26V may be provided by the UD in order to achieve 24V at the LID due to voltage drop in the cables. Once an indication that the target CV voltage has been met at the load is received, the UD can set its maximum current to the current measured at that time. As a safety feature, some embodiments of a LID may include an over-voltage protection to ensure that the CV voltage level of the load is not exceeded.

Some embodiments may include a light sensor to determine brightness from the LED load. The light sensor may be coupled to the LID or the driver itself and used to determine how much power to provide to the load. Power limits of the LED load would be observed, however, to make sure the desired light level isn't beyond what the light/luminaire can deliver.

Reference now is made in detail to the examples illustrated in the accompanying drawings and discussed below.

FIG. 12 shows a block diagram of an embodiment of a system 1200 providing constant current (CC) drive for a constant voltage (CV) load 1230. The system includes a driver 1210 and a CV load 1230. In embodiments, the driver 1210 may be selected to match the CV voltage of the load 1230 or the driver may be configured at a time of installation to match the CV voltage of the load 1230, manually, automatically, or programmatically, depending on the embodiment. The driver 1210 receives power from power source 1201 which can be any type of power source, but may be an alternating current AC source connected to a power grid (e.g. 1 lOVAC power), a battery, a photovoltaic cell, or any other power source. The load 1230 may include one or more light-emitting diodes (LEDs) which may be arranged in any topology including, but not limited to, multiple LEDs coupled in series (i.e. a string of LEDs), multiple LEDs coupled in parallel, and multiple strings of LEDs coupled in parallel. In some embodiments, the load 1230 may be a commercially available LED strip which can be cut at predetermined points to a variable length. In embodiments, the load 1230 may be designed to be driven at a particular voltage (i.e. a CV load). The CV voltage can be any predetermined voltage, depending on the embodiment, but may be 5VDC, 12VDC, 24VDC, or 48VDC as non-limiting examples. In the case of the LED strip, the CV voltage for a particular strip may remain constant even for different lengths of the strip.

The driver 1210 may include a voltage-regulated power supply 1212, which may also be referred to as a constant voltage (CV) supply. The power supply 1212 may be able to provide a particular voltage level for any current load up to the maximum specified load for that embodiment. So for example, a 60 W, 12 VDC power supply 1212 may be able to provide a steady 12 VDC at any current level up to 5 A.

The driver 1210 may also include a processor 1218, such as a microcontroller with integrated memory containing a program to control the driver 1210. In some embodiments, the processor 1218 may be coupled to a control interface 1205 to provide input to the processor 1218. The control interface 1205 can be any communication path that allows the processor 1218 to receive information about how to control the load 1230, and may be coupled to a user interface, such as a knob, slider, keyboard, touchscreen, or buttons, or may be coupled to a remote control which communicates over an infrared (IR) or radio-frequency (RF) signal. In some embodiments, the control interface 1205 may be a computer network, such as an internet protocol (IP) over Ethernet or Wi-Fi. Alternatively, the control interface 1205 may be a home automation network such as Z-Wave or Zigbee or may be a personal area network such as Bluetooth.

The processor 1218 may control a current limiting device 1213 which can receive a voltage-regulated power input and provide a current-regulated output. In some embodiments, the CV power supply 1212 and the current limiter 1213 may be integrated into a single module that can act as either a voltage-regulated power source or a current-regulated power source, under control of the processor 1218. The current flowing from the current limiter 1213 may be measured by using a shunt resistor 1214 to carry the power from the current limiter 1213 to the load 1230 and measuring the voltage across the shunt resistor 1214 using the analog-to-digital converter (ADC) to provide the measurement to the processor 1218. Other embodiments may use other techniques to measure the current including, but not limited to, a current transformer, a Hall effect sensor, a magneto-resistive sensor, a fiber optic current sensor, instrumentation in the voltage-regulated power supply 1212, instrumentation in the current limiter 1213, a dedicated energy measurement chip such as a CS5463 from Cirrus Logic, or a dedicated energy measurement module integrated into the processor 1218 such as the ESP430 module in a MSP 430 from Texas Instruments.

FIG. 13 shows voltage and current waveforms 1300 for the system 1200 providing constant current (CC) drive for a constant voltage (CV) load 1230. Voltage waveforms 1320, 1340, 1342, 1344 are shown in broken lines and current waveforms 1330, 1350, 1352, 1354 are shown in solid lines. Voltage/ current levels are qualitatively indicated along the vertical axis and time advances toward the right on the horizontal axis. At some point, the driver 1210 may determine a maximum current (Imax) for the load 1230. This may occur upon application of power to the driver 1210, as a part of a boot-up process (or reset process) for the processor 1218, in response to a manual input to the driver 1210, or at any other time, dependent on the embodiment. In the example shown, the driver 1210 begins to determine Imax at time tO 1310 by turning on the CV power supply 1212 to provide the full CV voltage 1320 and not limiting the current with the current limiter 1213 to allow current 1330 to flow through the load 1230.

The current 1330 also flows through the shunt resistor 1214 which allows the processor 1218 to measure a voltage across the shunt resistor 1214 which is proportional to the current 1330. The processor 1218 may determine the current level based on a calibration of the voltages across the shunt resistor 1214 so that the processor 1218 can determine a current limiter 1213 setting to match the current level 1330 based on an equation or a table stored in the memory of the processor 1218. But in some embodiments, the processor 1218 may vary the settings of the current limiter 1213 until the voltage across the shunt resistor 1214 begins to drop to determine the setting of the current limiter 1213 that matches the current level 1330. The setting for the current limiter 1213 the matches the current level 1330 may become the setting for Imax. After Imax has been determined at time tl 1311, the processor 1218 may, in some embodiments, turn off the CV power supply 1212 or set the current limiter 1213 to 0 A to turn off the load 1230, but in other embodiments, the CV power supply 1212 may be left on at time tl 1311 and the current limiter 1213 set to a predetermined level which may be any level between 100% and 0% of Imax, inclusive.

At time t2 1312 the driver may receive a command through the control interface 1205 to start a slow ramp from 0% to 100% brightness. In some embodiments this may be done using a single command, but other embodiments may send multiple commands, such as 100 commands, each a predetermined time apart (dependent upon the desired ramp speed) indicating a brightness level 1% higher than the previous command. This turn-on ramp is created by the processor controlling the current limiter 1213 to generate the current ramp 1350 between time t2 1312 and time t3 1313. As the current linearly ramps up, note that the voltage 1340 increases non-linearly due to the physics of LEDs. Once Imax 1352 is reached at time t3 1313, the voltage 1342 has reached the full CV voltage.

At time t4 1314 the driver 1210 may receive a command to set the brightness to 40% over the control interface 1205 and respond by setting the current to 40% of Imax using the current limiter 1213. Depending on the embodiment, the processor 1218 may be able to determine the settings for the current limiter 1213 corresponding to the 40% of Imax current level algorithmically or using a table, but in other embodiments, a control loop using the voltage across the shunt resistor 1214 as the feedback may be implemented in the processor 1218 to control the current limiter 1213. As a result of limiting the current 1354 through the load 1230 to 40%, the voltage 1344 may drop below the CV voltage, but is still much more than 40% of the CV voltage due to the non-linear response of the LED 1230 to current.

At time t5 1315 the driver 1210 may receive a command over the control interface 1205 to turn off the LED 1230 and the processor 1218 may respond by shutting off the CV power supply 1212 or telling the current limiter 1213 to set the current to 0 A. As additional commands may be received and processed by the driver 1210, the current to the load 1230 may vary to any level between 0A and Imax but the voltage level is not allowed to exceed the CV voltage for the load 1230 because that is the maximum voltage provided by the CV power supply 1212, although some embodiments may include voltage protection circuitry to protect against voltage spikes that may be caused by inductance of cables carrying the current to the load 1230.

FIG. 14 shows a block diagram of an alternative embodiment of a system 1400 providing CC drive for a CV load 1430. The system includes a driver 1410 and a CV load 1430. In embodiments, the driver 1410 may be selected to match the CV voltage of the load 1430 or the driver may be configured at a time of installation to match the CV voltage of the load 1430, manually, automatically, or programmatically, depending on the embodiment. In some embodiments, the driver 1410 may include an RFID tag holding information about what type of load to drive from the driver 1410 (e.g. CV or CC and/or a voltage or current level) where the RFID tag was programmed using an RFID writer at the factory or in the field using a smartphone. The driver 1410 receives power from power source 1401 which can be any type of power source, but may be an alternating current AC source connected to a power grid (e.g.

110 VAC power), a battery, a photovoltaic cell, or any other power source. The load 1430 may include one or more light-emitting diodes (LEDs) which may be arranged in any topology including, but not limited to, multiple LEDs coupled in series (i.e. a string of LEDs), multiple LEDs coupled in parallel, and multiple strings of LEDs coupled in parallel. In some embodiments, the load 1430 may be a commercially available LED strip which can be cut at predetermined points to a variable length. In embodiments, the load 1430 may be designed to be driven at a particular voltage (i.e. a CV load). The CV voltage can be any predetermined voltage, depending on the embodiment, but may be 5VDC, 12VDC, 24VDC, or 48VDC as non -limiting examples. In the case of the LED strip, the CV voltage for a particular strip may remain constant even for different lengths of the strip.

The driver 1410 may include a current-regulated power supply 1412, which may also be referred to as a constant current (CC) supply even though the current level may be varied under control of the processor 1418. The power supply 1412 may be able to provide a specified current level at any voltage up to the CV voltage of the load and up to a maximum specified power for that embodiment. So for example, a 60 W, 5 A max power supply 1412 may be able to provide a specified current of up to 5 A at up to the 12 VDC for a 12 VDC CV load 1430.

The driver 1410 may also include a processor 1418, such as a microcontroller with integrated memory containing a program to control the driver 1410. In some embodiments, the processor 1418 may be coupled to a control interface 1405 to provide input to the processor 1418. The control interface 1405 can be any communication path that allows the processor 1418 to receive information about how to control the load 1430, and may be coupled to a manual input, such as a knob, slider, keyboard, touchscreen, or buttons, or may be coupled to a remote control which communicates over an infrared (IR) or radio-frequency (RF) signal. In some embodiments, the control interface 1405 may be a computer network, such as an internet protocol (IP) over Ethernet or Wi-Fi. Alternatively, the control interface 1405 may be a home automation network such as Z-Wave or Zigbee or may be a personal area network such as Bluetooth in some embodiments.

As indicated earlier the processor 1418 may control the current-regulated power supply 1412. The current flowing from the power supply 1412 may be determined directly from the control of the power supply 1412, such as a digital interface where a particular current level is provided to the power supply 1412 by the processor 1418, or may be measured by using any method and used in a feedback control loop to control the current flowing from the power supply 1412. An ADC 1416 may be used to measure the voltage of the output 1414 of the power supply 1412 and provide the measurement to the processor 1418, although in other embodiments, instrumentation in the power supply 1412 may be able to provide information about the present voltage level of its output to the processor 1418. FIG. 15 shows voltage and current waveforms 1500 for the system 1400 providing constant current (CC) drive for a constant voltage (CV) load 1430. Voltage waveforms 1522, 1542, 1544 are shown in broken lines and current waveforms 1530, 1532, 1552-1554 are shown in solid lines. Voltage/ current levels are qualitatively indicated along the vertical axis and time advances toward the right on the horizontal axis. At some point, the driver 1410 may determine a maximum current (Imax) for the load 1430. This may occur upon application of power to the driver 1410, as a part of a boot-up process (or reset process) for the processor 1418, in response to a manual input to the driver 1410, or at any other time, dependent on the embodiment. In the example shown, the driver 1410 begins to determine Imax at time tO 1510 by gradually ramping up the current 1530 provided by the power supply 1412 until the CV voltage 1522 is reached. At that time, the current 1532 provided by the power supply 1412 is determined to be Imax. After Imax has been determined at time tl 1511, the processor 1418 may, in some embodiments, turn off the power supply 1412 to turn off the load 130, but in other embodiments, the power supply 1412 may be set to a predetermined level at time tl 1511 which may be any level between 100% and 0% of Imax, inclusive.

At time t2 1512 the driver may receive a command through the control interface 1405 to start a slow ramp from 0% to 100% brightness. This turn-on ramp is created by the processor 1418 controlling the power supply 1412 to generate the current ramp 1550 between time t2 1512 and time t3 1513. Once Imax 1552 is reached at time t3 1513, note that the voltage 1542 has reached the full CV voltage.

At time t4 1514 the driver 1410 may receive a command to set the brightness to 40% over the control interface 1405 and respond by setting the current of the power supply 1412 to 40% of Imax which causes the voltage 1544 to drop somewhat below the CV voltage. At time t5 1515 the driver 1410 may receive a command over the control interface 1405 to turn off the LED 1430 and the processor 1418 may respond by shutting off the power supply 1412. As additional commands may be received and processed by the driver 1410, the current to the load 1430 may vary to any level between 0A and Imax but the voltage level is not allowed to exceed the CV voltage for the load 1430. Some embodiments may include a separate voltage limiting circuit as a safety measure.

FIG. 16 shows a block diagram of an embodiment of a system 1600 providing CC drive for a CV load using a load identification device (LID) 1430. The system includes a driver 1610 and a CV load 1640 with a LID 1630 positioned between them. A cable 1620 couples the LID 1630 to the driver 1610 in the embodiment shown. The cable 1620 may be any type of cable, depending on the embodiment, but may be a cable 1620 with four twisted pair conductors in some embodiments, such as a category 3, category 5, category 5e, category 6, or category 7 cable which is commonly used for Ethernet networking. The cable 1620 may couple to the driver 1610 and the LID 1630 using any electrical connection mechanism, including any type of connector, but in some embodiments, an RJ-45 connector with 8 contacts may be used on both ends of the cable 1620.

The LID 1630 includes an interface to the cable 1620, which may be a female RJ-45 connector in some embodiments, an interface to the LED device(s) 1640, which may be an LED strip connector in some embodiments, a power conductor 1634 connecting a power connection of the cable interface to a power connection of the LED interface, and circuitry 1632 coupled to the cable interface, to provide drive information about the LED device 1640 through the cable 1620. In various embodiments, the circuitry may include one or more switches or resistors coupled between connections of the cable interface, such as the resistor 1632 shown. In other

embodiments, the circuitry may include a memory device, such as (but not limited to) a flash memory with a serial interface or a radio-frequency identification (RFID) tag, storing the drive information and coupled to at least one connection of the cable interface. The circuitry may also include a sense conductor 1636 connected to the power conductor 1634 and to a sense connection 1626 of the cable interface. The circuitry may include a current sensor coupled to a sense connection 1624 of the cable interface configured to sense a current flowing through the power conductor 1634 in some embodiments.

The LED driver 1610 includes a drive interface for an LED load 1619 and a current regulator 1612 coupled between a source of electrical power 1601 and the drive interface 1619.

In some embodiments. The source of electrical power 1601 may be a connection to an AC power source, such as a wall outlet or wired connection to electrical wiring of a building, and the current regulator 1612 may be a current-regulated DC power supply. In other embodiments, the source of electrical power may be a voltage-regulated DC power supply and the current regulator may provide a current limiting function on that DC power supply’s output. The LED drive 1610 also includes a control interface 1605 and a processor 1618 coupled to the current regulator 1613 and the control interface 1605, as well as a non-transitory storage medium 1617 (e.g. a semiconductor memory) storing one or more instructions that in response to being executed by the processor 1618 cause the LED driver to perform one or more methods described herein. The memory may be embedded in the processor 1618 or may be a separate component, depending on the embodiment. In embodiments, the driver 1610 may determine a CV voltage level or a CC current level for the load 1640 based on its connection to the LID 1630 and the driver 1610 may be able to function with a variety loads having different CV voltages or CC currents. The LID 1630 may signal characteristics of the load 1640 using any technique, including, but not limited to, using different values of resistance for a resistor 1632 between a pair of conductors on the cable 1620, providing different sets of pull-up or pull-down resistors on wires of the cable 1620, different connections between wires of the cable 1620 using switches, jumpers, or traces on a printed circuit board, providing an analog voltage on one or more wires of the cable 1620, sending a digital message using any serial or parallel communication protocol using one or more of the wires of the cable 1620, any other communication techniques, or any combination thereof. In some embodiments, the LID 1630 may provide the information about the load 1640 before the driver 1610 provides any power to the LID 1630. In other embodiments, the driver 1610 may provide low-voltage power, lower than is normally used to power an LED load, such as power at a voltage lower than 5 V, to power circuitry on the LID 1630 which then sends the information to the driver 1610. In other embodiments, circuitry on the LID 1630 may work in conjunction with the driver 1610 to help the driver 1610 determine the information.

In the embodiment shown, the LID 1630 includes a resistor 1632 selected to convey information about the load 1640. The resistor 1632 may be loaded at the factory and the LID 1630 marketed to work with one specific type of load 1640 (e.g. a 24 VDC CV load), but in other embodiments, the resistance 1632 may be field configurable using jumpers, selection of one of a set of resistors to load into a socket, or using switches on the LID 1630 to select one of several resistors. The processor 1618 may be able to determine the value of resistor 1632 by applying a voltage and measuring a current through the resistor 1632, or by providing a set current and measuring the voltage created across the resistor 1632. Any method can be used to measure the resistance. Table 1 below provides one non-limiting example of how resistor values may be used to indicate information about the load 1640.

CC 1000 mA 383 kQ

Table 1

The driver 1610 receives power from power source 1601 which can be any type of power source, but may be an alternating current (AC) source connected to a power grid (e.g. 1 lOVAC power), a battery, a photovoltaic cell, or any other power source. The load 1640 may include one or more light-emitting diodes (LEDs) which may be arranged in any topology including, but not limited to, multiple LEDs coupled in series (i.e. a string of LEDs), multiple LEDs coupled in parallel, and multiple strings of LEDs coupled in parallel. In some embodiments, the load 1640 may be a commercially available LED strip which can be cut at predetermined points to a variable length.

The driver 1610 may include a current-regulated power supply 1612, which may also be referred to as a constant current (CC) supply even though the current level may be varied under control of the processor 1618. Other embodiments of a driver configured to work with a LID 1630 may utilize a CV supply with a current limiter similar to the driver 110 shown in FIG. 1. The power supply 1612 may be able to provide a specified current level at any voltage up to a CV voltage of the load and up to a maximum specified power for that embodiment. So for example, a 60 W, 5 A max power supply 1612 may be able to provide a specified current of up to 5 A at up to the 12 VDC for a 12 VDC CV load 1640. In some embodiments, the driver 1610 may be able to drive a load 1640 that is a CC load up to the maximum current capability of the power supply 1612.

The driver 1610 may also include a processor 1618, such as a microcontroller with integrated memory containing a program to control the driver 1610. In some embodiments, the processor 1618 may be coupled to a control interface 1605 to provide input to the processor 1618. The control interface 1605 can be any communication path that allows the processor 1618 to receive information about how to control the load 1640, and may be include to a user interface, such as a knob, slider, keyboard, touchscreen, or buttons, or may be coupled to a remote control which communicates over an infrared (IR) or radio-frequency (RF) signal. The user interface or the remote control may be used to receive a user input to provide to the processor 1618. In some embodiments, the control interface 1605 may be a computer network, such as an internet protocol (IP) over Ethernet or Wi-Fi. Alternatively, the control interface 1605 may be a home automation network such as Z-Wave or Zigbee or may be a personal area network such as Bluetooth in some embodiments. As indicated earlier the processor 1618 may control the current-regulated power supply 1612. The current flowing from the power supply 1612 may be determined directly from the control of the power supply 1612, such as a digital interface where a particular current level is provided to the power supply 1612 by the processor 1618, or may be measured by using any method and used in a feedback control loop to control the current flowing from the power supply 1612. Similarly to the processor 1410 of FIG. 14 as shown by the waveforms 1500 of FIG. 15, the processor 1618 may ramp an amount of current provided to the load 1640 until the CV voltage level is met for a CV load 1640 to determine Imax. An ADC 1616 may be used to measure the voltage of the power conductor 1634 in the LID 1630 (or at the load 1640) and provide the measurement to the processor 1618. This may be accomplished by connecting a sense wire 1626 on the cable 1620 to the power rail at the LID 1630 and using the ADC 1616 to measure the voltage at the sense wire. This allows the driver 1610 to compensate for voltage losses in the cable 1620. In other embodiments, the LID 1630 may include voltage measurement circuitry and send a digital indication of the voltage level to the driver 1610. In other embodiments, the LID 1630 may not signal its CV voltage to the driver 1610, but use on-board circuitry to compare the drive voltage to its CV voltage and send a binary signal across the cable 1620 to the processor 1618 once the voltage level matches the specified CV drive level.

Depending on the length of the cable 1620, the gauge of the wires 1622, 1624 carrying power in the cable 1620, and the number of wires used in the cable 1620 to carry power, non-negligible power may be consumed by the cable 1620 itself resulting in a voltage crop across the cable 1620. So for example, if the load 1640 is a 24 VDC load consuming 60 W, 5 A of current is flowing through the cable 1620 and if the resistance of the power conductors of the cable is 0.5 W, the voltage drop across the cable 1620 would be 2.5 V. Thus the voltage of the power 1614 in the driver may be 2.5 V higher than the voltage of the power conductor 1634 at the load 1640, so it may be helpful to measure the voltage at the load 1640 instead of at the driver 1610.

Similarly to the driver 1410 of FIG. 14, the driver 1610 may respond to commands received over the control interface 1605 by controlling the amount of current provided by the power supply 1612 to the load 1640 to control its brightness. The value of Imax may be used in conjunction with the desired brightness level received in the command to determine how much current to provide to the load 1640. In some embodiments, the driver 1610 may be coupled to a light sensor 1650 to measure the brightness of the load 1640. Information collected from the brightness sensor may be used to provide more accurate control of the brightness of the load 1640. FIG. 17 shows a block diagram of an embodiment of a system 1700 providing CC drive for a CV load 1741, 1742 using centralized power source 1710. The system 1700 may also include CC loads 1749 driven from the same power source 1710. The power source 1710 may be referred to as a universal driver (UD) and may also be compliant with IEEE power-over-ethemet (PoE) standards in some embodiments as power sourcing equipment (PSE). The UD 1710 is coupled to a power source 1701, which may be any type of power source, including, but not limited to, 1 lOVAC power from a standard electrical outlet. The UD 1710 is also coupled to a computer network 1705, such as, but not limited to, an Ethernet network of any type or a Wi-Fi network. The UD 1710 may have any number of connectors 1711-1719 capable of driving an LED load. In some embodiments, one or more of the connectors 1711-1719 may also be an Ethernet port and may support network equipment compliant with IEEE PoE standards.

In embodiments, cables 1721-1729 may be used to couple LIDs 1731-1739 to connectors 1711-1719 of the UD 1710. The cables 1721-1729 may be compliant with IEEE PoE standards in some embodiments. A LID 1731-539 may include circuitry to communicate information about an LED load 1741-1749 to the UD 1710. Various embodiments may use different types of circuitry, including, but not limited to different resistors, a non-volatile memory on the LID 1731-1739 that can be read by the UD 1710 over a cable 1721-1729 or read by a circuitry on the LID 1731-1739 and sent to the UD 1710. In at least one embodiment, the LID includes an RFID tag holding the information where the RFID tag was programmed using an RFID writer at the factory or in the field using a smartphone.

In the example shown, the first LID 1731 is configured to support an LED load 1741 that is a CV 12VDC load, the second LID 1732 is configured to support an LED load 1742 that is a CV 24VDC load, and the third LID 1739 is configured to support an LED load 1749 that is a CC 1A load. Once the UD 1710 receives the information from the LIDs 1731-1739, it knows the maximum current of the third LED load 1749 is 1 A but it does not know the maximum current of the other two LED loads 1741, 1742. The UD 1710 may utilize techniques described herein to determine maximum currents for the first LED load 1741 and the second LED load 1742.

Once the information about the LED loads 1741-1749 has been determined, the UD 1710 may expose the existence of the LED loads 1741-1749 as individual devices on the network 1705. In some embodiments, the UD 1701 may group two or more of the LED loads 1741-1749 as a single device exposed on the network. An IP address may be allocated for each individual LED load 1741-1749, an aggregate of LED loads 1741-1749, or as functions within the UD 1710 which may have its own IP address. Any discovery protocol may be used to expose the LED loads 1741-1749 and its capabilities to other devices on the network, including, but not limited to, IP -based discovery protocols such as universal plug-and-play (UPnP), simple service discovery protocol (SSDP - which uses UPnP protocols), multicast domain name service (mDNS), or AllJoyn (which utilizes mDNS). Any data structure, protocol, or technique can be used to specify the functionality and control parameters of the LED loads 1741-1749 through the discovery service, including, but not limited to, DotDot from the Zigbee Alliance, lightweight machine-to-machine protocol (LWM2M) from the Open Mobile Alliance (OMA), specifications from the Open Connectivity Foundation (OCF), Mesh Objects, JavaScript Object Notation (JSON) objects, extensible Markup Language (XML) objects, other standards, data structures, or mechanisms, or combinations thereof. Once the existence and capabilities of the LED loads 1741-1749 are exposed on the network, other applications, devices, or entities may control the LED loads 1741-1749 through the UD 1710, but the exact mechanisms used to do that, which may be standards-based or proprietary, are beyond the scope of this disclosure, although examples might include the ability to turn the LED loads 1741-1749 on or off, set a brightness level of the LED loads 1741-1749, control a color or color temperature of the LED loads 1741- 1749, or query a status of the LED loads 1741-1749.

FIG. 18 is a flowchart 1800 of an embodiment of a method for providing constant current (CC) drive for a constant voltage (CV) load. The flowchart starts with providing power 1805 to the CV load at the specified CV voltage level and determining 1810 a current (Imax) of the load, which may be one or more LED arranged in any topology, when the voltage provided to the load is set to the specified CV voltage level. The maximum current may be determined each time that power is provided to the drive device (i.e. a power-up reset), at regular intervals, in response to a manual input (e.g. a button push), in response to receipt of a calibration command from a computer network or a remote control, upon detection of a change in the CV load, or based on any other stimulus.

The CV voltage level used may be predetermined or may be received as a user input. In some embodiments, information indicating the CV voltage level may be received from the CV load. The information may be received by any technique, including, but not limited to, measuring one or more resistance values of the LED load or using a serial communication protocol. In some embodiments, a load identification device coupled to one or more LEDs may provide the drive information through a cable.

Imax may be determined using any technique, but a first embodiment may provide a power signal at the CV voltage from a voltage-regulated power supply and measure 1812 the current, which is interpreted as Imax. The measurement may be performed using instrumentation included in the power supply, by measuring a voltage across a shunt resistor included in the current path to the load, or by using an inductive current sensor coupled to the current path (e.g. a current sensing coil surrounding a conductor carrying the first electrical power to the LED load). A second embodiment may use a current-regulated power supply and measure 1814 the voltage across the load. The voltage may be measured at the source, or to be more accurate, at the load, depending on the embodiment. The power source may ramp the current up until the designated CV voltage level is met, and the current at that time is interpreted as Imax. In some embodiments that include a brightness sensor, a brightness reading may be taken at the time the Imax is determined to determine a maximum brightness level.

The driver may receive brightness information 1820 indicating a desired brightness of the load. In some embodiments, the brightness may simply be an on/off command or the brightness may be indicated as a percentage of maximum. In other embodiments, the brightness may be indicated as a particular lux level and the driver may be coupled to a brightness sensor. The brightness information may be received from a manual input (e.g. a rotatable knob or a linear slider), an analog voltage signal (e.g. a 0-10 VDC signal), a command received over a digital communications interface (e.g. a computer network), a command received as an infrared (IR) or radio-frequency (RF) signal from a remote control, or by any other technique.

Once the brightness information has been received 1820, a current may be calculated 1830 based on the desired brightness information and Imax. In some embodiments, a linear brightness response to current may be assumed, so that if brightness is provided as a percentage of maximum brightness, the brightness percentage is multiplied by Imax to calculate the desired current. In other embodiments, a brightness curve, in the form of an equation or a lookup table, may be used to calculate the desired current from the desired brightness. In systems where an absolute brightness is provided, the desired current may be based on Imax multiplied by the ratio of desired brightness to maximum brightness.

The calculated current is then provided 1840 to the load to turn provide the desired brightness from the LEDs. In some systems, a current limiting device on an output of a voltage- regulated power supply may be used to limit the current, but in other systems, a current-regulated power supply may be used so that a control signal is provided to the power supply to set the current to the desired level. In some systems, feedback from the brightness sensor may be used to fine tune the brightness after the calculated current is provided to the load. In embodiments, new brightness information may be received 1820 at any time. A new current may then be calculated 1830 and provided 1840 to the load. It should be noted that the load may be‘turned on’ by setting the current to Imax or‘turned off by setting the current to 0 A.

FIG. 19 is a flowchart 1900 of an embodiment of a method for universal driving of an LED load. The method commences with receiving 1902 drive information from the LED load. Any technique may be used to receive the drive information from the LED load, some of which are described above. The drive information is examined to determine 1904 whether the LED load has a constant voltage (CV) characteristic or a constant current (CC) characteristic. Different action may be taken 1906 depending on whether the LED load has a CV characteristic or a CC characteristic.

If the LED load has the CV characteristic, a CV level is determined 1910 based on the drive information and electrical power is provided 1912 to the LED load at the CV level that is based on the drive information. The power may be set to the CV level by using a voltage regulated power supply, or by ramping up the current until the CV level is equaled if a power supply that can only regulate the current is used. If the LED load has the CC characteristic, a CC level is determined 1920 based on the drive information and electrical power is provided 1922 to the LED load at the CC level that is based on the drive information.

In some embodiments a current level may be determined 1914 (e.g. measured) for the LED load while the CV voltage level is applied to the LED load in response to said determining that the LED load has the CV characteristic and set as a CC level for the CV load. Brightness control information for the LED load may be received 1930 and a current level calculated 1932 based on the brightness control information and the CC level for the load. Electrical power may then be provided 1934 to the LED load regulated to the calculated current level regardless of whether the LED load has the CV characteristic or the CC characteristic. This may be repeated as new brightness control information is received 1930.

Examples of various embodiments of CC Dimming of CV Loads are described in the following paragraphs:

Embodiment CL A method of driving an LED load, the method comprising:

providing electrical power to the LED load at a first voltage level; determining a first current level consumed by the LED load while the first voltage level is applied to the LED load;

receiving brightness control information for the LED load; calculating a second current level based on the first current level and the brightness control information; and providing the electrical power to the LED load regulated at the second current level; wherein a second voltage level of the electrical power provided to the LED with the second current level is less than the first voltage level.

Embodiment C2. The method of embodiment Cl, wherein said providing and said determining are performed in response to a power-up reset.

Embodiment C3. The method of embodiment Cl or C2, wherein the first voltage level is predetermined.

Embodiment C4. The method of embodiment Cl or C2, further comprising receiving a user input to indicate the first voltage level.

Embodiment C5. The method of embodiment Cl or C2, further comprising receiving drive information from the LED load indicating the first voltage level.

Embodiment C6. The method of embodiment C5, further comprising measuring one or more resistance values of the LED load to receive the drive information.

Embodiment C7. The method of embodiment C5 or C6, further comprising communicated with the LED load using a serial communication protocol to receive the drive information.

Embodiment C8. The method of any of embodiments C5 through C7, the LED load comprising a load identification device coupled to one or more LEDs, the drive information received from the load identification device through a cable.

Embodiment C9. The method of any of embodiments Cl through C8, said determining the first current level comprising measuring the first current level using a shunt resistor in series with the LED load or a current sensing coil surrounding a conductor carrying the first electrical power to the LED load.

Embodiment CIO. The method of any of embodiments Cl through C8, the LED load comprising a load identification device coupled to one or more LEDs; the load identification device comprising a current sensor said measuring the first current level comprising receiving current information from the current sensor through a cable coupled to the load identification device.

Embodiment Cl 1. The method of any of embodiments Cl through C8, said determining the first current level comprising querying a current-regulated power supply that is providing the first electrical power to the LED load.

Embodiment C12. The method of any of embodiments Cl through C8, further comprising: providing the electrical power to the LED load at a regulated current level using a variable current-regulated power supply; measuring an unregulated voltage level provided to the LED load at the regulated current level; increasing the regulated current level until the unregulated voltage level is equal to the first voltage level; and determining the first current level to be the regulated current level.

Embodiment C13. The method of embodiment Cl 2, said measuring the unregulated voltage level comprising measuring a voltage on the load identification device through a sense wire; wherein a single cable coupled to the load identification device includes both the sense wire and a conductor carrying said provided electrical power.

Embodiment C14. The method of any of embodiments Cl through C13, further comprising: receiving drive information from the LED load; determining whether the LED load has a constant voltage load characteristic or a constant current load characteristic based on the drive information; and providing the electrical power to the LED load at a third current level that is based on the drive information in response to said determining that the LED load has the constant current load characteristic; wherein said providing the electrical power to the LED load at the first voltage level is done in response to said determining that the LED load has the constant voltage load characteristic, the first voltage level set based on the drive information.

Embodiment Cl 5. A method of driving an LED load, the method comprising:

receiving drive information from the LED load; determining whether the LED load has a constant voltage characteristic or a constant current characteristic based on the drive information; providing electrical power to the LED load at a first voltage level that is based on the drive information in response to said determining that the LED load has the constant voltage characteristic; and providing the electrical power to the LED load at a second current level that is based on the drive information in response to said determining that the LED load has the constant current characteristic.

Embodiment Cl 6. The method of embodiment Cl 5, further comprising: determining a first current level consumed by the LED load while the first voltage level is applied to the LED load in response to said determining that the LED load has the constant voltage characteristic; receiving brightness control information for the LED load; calculating a third current level based on the brightness control information and either the first current level or the second current level; and providing the electrical power to the LED load regulated to the third current level regardless of whether the LED load has the constant voltage characteristic or the constant current characteristic. Embodiment Cl 7. At least one non-transitory machine readable medium comprising one or more instructions that in response to being executed on a computing device cause the computing device to carry out a method according to any one of embodiments Cl to Cl 6.

Embodiment Cl 8. A load identification device comprising: a first interface for an

LED device; a second interface for a power cable; a power conductor connecting a power connection of the first interface to a power connection of the second interface; and circuitry, coupled to the second interface, configured to provide drive information about the LED device through the power cable.

Embodiment Cl 9. The load identification device of embodiment Cl 8, the circuitry comprising one or more switches or resistors coupled between connections of the second interface.

Embodiment C20. The load identification device of embodiment Cl 8, the circuitry comprising a memory device storing the information and coupled to at least one connection of the second interface.

Embodiment C21. The load identification device of embodiment C20, the memory device comprising a radio-frequency identification (RFID) tag.

Embodiment C22. The load identification device of any of embodiments C18 through C21, the circuitry comprising a sense conductor connected to the power conductor and to a sense connection of the second interface.

Embodiment C23. The load identification device of any of embodiments C18 through C21, the circuitry comprising a current sensor coupled to a sense connection of the second interface, the current sensor configured to sense a current flowing through the power conductor.

Embodiment C24. The load identification device of any of embodiments C18 through C23, the second interface comprising a female RJ-45 connector.

Embodiment C25. The load identification device of any of embodiments C18 through C24, the first interface comprising an LED strip connector.

Embodiment C26. An LED driver comprising: a drive interface for an LED load; a current regulator coupled between a source of electrical power and the drive interface; a control interface; a processor coupled to the current regulator and the control interface; and a memory, coupled to the processor, and storing one or more instructions that in response to being executed by the processor cause the LED driver to: provide electrical power to the drive interface at a first voltage level; determine a first current level flowing through the drive interface while the first voltage level is applied to the LED load; receive brightness control information through the control interface; calculate a second current level based on the first current level and the brightness control information; and provide the electrical power at drive interface regulated at the second current level by the current regulator wherein a second voltage level of the second electrical power provided to the drive interface with the second current level is less than the first voltage level.

Embodiment C27. The LED driver of embodiment C26, wherein the first voltage level is stored in the memory.

Embodiment C28. The LED driver of embodiment C26 or C27, further comprising a user interface, coupled to the processor and configured to provide an indication of the first voltage level.

Embodiment C29. The LED driver of any of embodiments C26 through C28, the one or more instructions, in response to being executed by the processor, further cause the LED driver to receive drive information through the drive interface indicating the first voltage level.

Embodiment C30. The LED driver of embodiment C29, the one or more instructions, in response to being executed by the processor, further cause the LED driver to measure one or more resistance values between conductors of the drive interface to receive the drive

information.

Embodiment C31. The LED driver of embodiment C29, the one or more instructions, in response to being executed by the processor, further cause the LED driver to communicate through the drive interface using a serial communication protocol to receive the drive information.

Embodiment C32. The LED driver of any of embodiments C26 through C31, the one or more instructions, in response to being executed by the processor, further cause the LED driver to measure the first current level using a shunt resistor in or a current sensing coil.

Embodiment C33. The LED driver of any of embodiments C26 through C31, the one or more instructions, in response to being executed by the processor, further cause the LED driver to query the current regulator to determine the first current level.

Embodiment C34. The LED driver of any of embodiments C26 through C31, further comprising an analog-to-digital converter; the one or more instructions, in response to being executed by the processor, further cause the LED driver to: provide the electrical power to the drive interface at a regulated current level; measure an unregulated voltage level of the electrical power at the regulated current level; increase the regulated current level until the unregulated voltage level is equal to the first voltage level; and determine the first current level to be the regulated current level.

Embodiment C35. The LED driver of embodiment C34, wherein the analog-to-digital converter is coupled to a sense connection of the drive interface that is separate from a power connection of the drive interface coupled to the current regulator.

Embodiment C36. The LED driver of any of embodiments C26 through C35, the one or more instructions, in response to being executed by the processor, further cause the LED driver to: receiving drive information from the LED load; determining whether the LED load has a constant voltage load characteristic or a constant current load characteristic based on the drive information; and providing the electrical power to the LED load at a third current level that is based on the drive information in response to said determining that the LED load has the constant current load characteristic; wherein said providing the electrical power to the LED load at the first voltage level is done in response to said determining that the LED load has the constant voltage load characteristic, the first voltage level set based on the drive information.

Embodiment C37. An LED driver comprising: a drive interface for an LED load; a regulator coupled between a source of electrical power and drive interface; a processor coupled to the current regulator and the control interface; and a memory, coupled to the processor, and storing one or more instructions that in response to being executed by the processor cause the LED driver to: receive drive information about the LED load through the drive interface;

determine whether the LED load has a constant voltage characteristic or a constant current characteristic based on the drive information; provide electrical power to the drive interface at a first voltage level that is based on the drive information in response to said determining that the LED load has the constant voltage characteristic; and provide the electrical power to the drive interface at a second current level that is based on the drive information in response to said determining that the LED load has the constant current characteristic.

Embodiment C38. The LED driver of embodiment C37, further comprising a control interface; the one or more instructions, in response to being executed by the processor, further cause the LED driver to: determine a first current level flowing through the drive interface while the first voltage level is provided in response to said determining that the LED load has the constant voltage characteristic; receive brightness control information through the control interface; calculate a third current level based on the brightness control information and either the first current level or the second current level; and provide the electrical power to the drive interface regulated to the third current level regardless of whether the LED load has the constant voltage characteristic or the constant current characteristic.

Embodiment C39. An article of manufacture comprising a non-transitory storage medium having instructions stored thereon that, if executed, result in: receiving drive

information from the LED load; determining whether the LED load has a constant voltage characteristic or a constant current characteristic based on the drive information; providing electrical power to the LED load at a first voltage level that is based on the drive information in response to said determining that the LED load has the constant voltage characteristic; and providing the electrical power to the LED load at a second current level that is based on the drive information in response to said determining that the LED load has the constant current characteristic.

Embodiment C40. The article of manufacture as in embodiment C39, wherein the instructions, if executed, further result in: determining a first current level consumed by the LED load while the first voltage level is applied to the LED load in response to said determining that the LED load has the constant voltage characteristic; receiving brightness control information for the LED load; calculating a third current level based on the brightness control information and either the first current level or the second current level; and providing the electrical power to the LED load regulated to the third current level regardless of whether the LED load has the constant voltage characteristic or the constant current characteristic.

As will be appreciated by those of ordinary skill in the art, aspects of the various embodiments may be embodied as a system, device, method, or computer program product apparatus. Accordingly, elements of the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, or the like) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a“server,”’’circuit,”“module,”“client,”“ computer,”“logic,” or“system,” or other terms. Furthermore, aspects of the various embodiments may take the form of a computer program product embodied in one or more computer-readable medium(s) having computer program code stored thereon.

Any combination of one or more computer-readable storage medium(s) may be utilized.

A computer-readable storage medium may be embodied as, for example, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or other like storage devices known to those of ordinary skill in the art, or any suitable combination of computer-readable storage mediums described herein. In the context of this document, a computer-readable storage medium may be any tangible medium that can contain, or store a program and/or data for use by or in connection with an instruction execution system, apparatus, or device. Even if the data in the computer-readable storage medium requires action to maintain the storage of data, such as in a traditional semiconductor-based dynamic random access memory, the data storage in a computer-readable storage medium can be considered to be non- transitory. A computer data transmission medium, such as a transmission line, a coaxial cable, a radio-frequency carrier, and the like, may also be able to store data, although any data storage in a data transmission medium can be said to be transitory storage. Nonetheless, a computer- readable storage medium, as the term is used herein, does not include a computer data transmission medium.

Computer program code for carrying out operations for aspects of various embodiments may be written in any combination of one or more programming languages, including object oriented programming languages such as Java, Python, C++, or the like, conventional procedural programming languages, such as the "C" programming language or similar programming languages, or low-level computer languages, such as assembly language or microcode. The computer program code if loaded onto a computer, or other programmable apparatus, produces a computer implemented method. The instructions which execute on the computer or other programmable apparatus may provide the mechanism for implementing some or all of the functions/acts specified in the flowchart and/or block diagram block or blocks. In accordance with various implementations, the program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server, such as a cloud- based server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider). The computer program code stored in/on (i.e.

embodied therewith) the non-transitory computer-readable medium produces an article of manufacture.

The computer program code, if executed by a processor causes physical changes in the electronic devices of the processor which change the physical flow of electrons through the devices. This alters the connections between devices which changes the functionality of the circuit. For example, if two transistors in a processor are wired to perform a multiplexing operation under control of the computer program code, if a first computer instruction is executed, electrons from a first source flow through the first transistor to a destination, but if a different computer instruction is executed, electrons from the first source are blocked from reaching the destination, but electrons from a second source are allowed to flow through the second transistor to the destination. So a processor programmed to perform a task is transformed from what the processor was before being programmed to perform that task, much like a physical plumbing system with different valves can be controlled to change the physical flow of a fluid.

Unless otherwise indicated, all numbers expressing quantities, properties, measurements, and so forth, used in the specification and claims are to be understood as being modified in all instances by the term“about.” The recitation of numerical ranges by endpoints includes all numbers subsumed within that range, including the endpoints (e.g. 1 to 5 includes 1, 2.78, p,

3.33, 4, and 5).

As used in this specification and the appended claims, the singular forms“a”,“an”, and “the” include plural referents unless the content clearly dictates otherwise. Furthermore, as used in this specification and the appended claims, the term“or” is generally employed in its sense including“and/or” unless the content clearly dictates otherwise. As used herein, the term “coupled” includes direct and indirect connections. Moreover, where first and second devices are coupled, intervening devices including active devices may be located there between.

The description of the various embodiments provided above is illustrative in nature and is not intended to limit this disclosure, its application, or uses. Thus, different variations beyond those described herein are intended to be within the scope of embodiments. Such variations are not to be regarded as a departure from the intended scope of this disclosure. As such, the breadth and scope of the present disclosure should not be limited by the above-described exemplary embodiments, but should be defined only in accordance with the following claims and equivalents thereof.