SIM connector with ferrite

FIELD OF THE INVENTION

The present invention generally relates to a flat substrate for an identification card, and a card comprising the same. It also relates to a system consisting of both an identification card and an identification card connector, an identification card connector and an identification card suitable for such a system.

BACKGROUND OF THE INVENTION

The present invention relates to an identification card having dual functionalities of RFID (radio frequency identification) and smart card (also called combi cards) and to an identification card connector suitable for such identification card. Identification tags using the RFID technology or the EAS technology are known. Such tags comprise an IC chip, in which information is stored, electrically connected to an antenna coil. In such identification tags, it has been known that the tags are activated by transmitting a radio wave having a predetermined frequency from a transmitting/receiving antenna.

As described in the prior art, a dual identification card having dual functionalities of RFID and smart card can be manufactured. Such a dual identification card comprises a flat substrate, having two opposite main faces, comprising a loop shaped antenna for contactless communication, disposed on at least one main face, and a plurality of contacts for establishing an electrical

connection by contact with a card reader terminal on one of said two main faces.

Such a dual identification card is typically to be used in a SIM card reader of a cell phone. The contacts of said dual identification card are then electrically connected by contact with the terminals of the connector of the SIM card reader. The loop shaped antenna of said identification card provides contactless communication of the cell phone by transmitting a radio wave having a predetermined frequency.

The presence of metal parts in the cell phone into which said identification card is inserted, like PCB ground plane or battery case, will drastically decrease the contactless communication distance. Thus, the present invention seeks to mitigate these drawbacks .

SUMMARY OF THE INVENTION

An object of the present invention is a system according to claim 1.

A system according to the invention permits to cancel interferences between the radio waves transmitted by the identification card and the metal parts of a cell phone, thanks to the ferrite sheet. Therefore, the contactless communication distance will not be as affected by the presence of metal parts as it was in the prior art. In some embodiments, one might also use one of the features or any possible combination of the features corresponding to claims 2-7.

In addition, the present invention provides an identification card connector according to claim 8.

In some embodiments, one might also use one of the features or any possible combination of the features corresponding to claims 9-11.

According to another aspect, the invention relates to an identification card according to claim 12.

In some embodiments, one might also use one of the features or any possible combination of the features corresponding to claims 13-15. According to another aspect, the invention relates to an SIM format card comprising an identification card according to the invention.

According to another aspect, the invention relates to a phone comprising a system according to the invention. According to another aspect, the invention relates to a phone comprising an identification card connector according to the invention.

BRIEF DESCRIPTION OF THE DRAWNINGS

Other characteristics and advantages of the invention will readily appear from the following description of embodiments, provided as non limitative examples and of the accompanying drawings . On the drawings :

Fig. 1 is a perspective view from the top of a SIM card connector according to an embodiment of the invention,

Fig. 2 is an exploded perspective view of a SIM card according to an embodiment of the invention,

Fig. 3 is a cross sectional view of the SIM card of Fig. 2,

Fig. 4 is a perspective view from the top of a part of the SIM card of Fig. 3,

Fig. 5 is a perspective view from the bottom of a part of the SIM card of Fig. 3, On all Figures, the same reference signs designate like or similar elements.

On Fig. 1, a SIM card connector 10 according to an embodiment of the invention for fixation into a phone P is shown. In this embodiment, the SIM card connector 10 includes a housing 12, eight electrical springs 14, two retaining members 16 and a ferrite sheet 18.

The housing 12 is made of plastic and is used as a basic component of the SIM card connector 10. The housing 12 includes lateral sides 121, 122. The housing also includes a front face 125 and a back face 126.

The housing includes on its first and second sides 121,122 two walls 20 that extends above the front face 125. The walls 20 are integrally formed in the housing 12.

The SIM card connector 10 represented on Fig. 1 can also include a metal sheet 17 stuck on the back face 126 of the housing 12. The metal sheet 17 is designed in such a way that it does not provide electrical contact between the electrical springs 14. The metal sheet 17 helps to better control the cell phone environment, in particular the printed circuit board ground plan.

The two retaining members 16 are integrally formed on the metal sheet 17 and are formed like hooks. Each of the retaining members 16 extends from the metal sheet 17 stuck on the back face 126 of the housing, along the walls 20 on the first and second sides 121, 122 respectively, to the front face 125. The retaining members 16 are designed so that they extend on the front face 125 face to face with each other and facing the electrical spring 14.

The ferrite sheet 18 is stuck on the surface of the front face 125 of the housing 12. The ferrite sheet 18 comprises a hole 22 of the size of the housing contact area 15. Therefore, when stuck on the surface of the front face 125, the ferrite sheet 18 covers all the surface of the front face 125 of housing 12 except on the contact area 15. The ferrite sheet 18 is for example composed of iron oxide (Fe2<04) and an oxide of metal such as manganese Mn and zinc Zn, or nickel Ni and zinc Zn or the like for canceling interference from electromagnetic waves and a magnetic field. Such ferrite sheets are commercially available from NEC, TDK or other suppliers.

The thickness of the ferrite sheet 18 is so that the electrical springs, on the front face 125 of the housing 12, project out of the hole 22, for example between 1 micrometer and 1 millimeter.

On Fig. 2, a SIM format card 24 is shown. In this embodiment, the SIM card 24 includes a protective sheet 26, a substrate 28 and a carrier 30. The substrate 28, includes two main faces, a top main face 281 and a bottom main face 282.

As shown in a general manner in Fig. 2 and in more detailed manner on Fig. 3 and 4, the top main face 281 of the substrate 28 includes a SIM card contact area 32. Said SIM card area 32 is suitable for establishing an electrical connection by contact between the SIM format card 24 which comprise the flat substrate 28 and terminals of a complementary contacting card reader.

The substrate 28 also comprises an antenna area 34 suitable for contactless communication with a suitable contactless complementary device. As shown on Fig. 3, the antenna area 34 may extend on the top main face 281 and on the bottom main face 282 of the substrate 28.

The protective sheet 26, has a window 36 of at least the size of the SIM card contact area 32. When the protective sheet 26 covers the substrate 28, the window 36 permits, contact between the SIM card contact area 32 and terminals of a complementary contacting card reader.

The carrier 30 is made of plastic and designed to receive the substrate 28. The carrier 30 includes a bottom part 301 and an external wall 302 extending on the perimeter of the bottom part 301. The SIM card 24 is assembled by placing the bottom main face 282 of the substrate 28 on the bottom part 301 of the carrier 30. The substrate 28 is held in place by the external wall 302. In order to protect the antenna area 34 the protective sheet 26 is placed and sealed onto the upper face of the external wall 302 of the carrier 30. The protective sheet is placed on the substrate so that the window 36 of said protective sheet 26 faces the SIM card contact area 32 of the substrate 28.

When a SIM card is inserted into the SIM card connector 10, its SIM card contact area (reference 32 on Fig. 2) faces the housing contact area 15 of the housing 12. The SIM card is held in position between the ferrite sheet 18, the walls 20 and the engaging members 16. The SIM card is placed on the front face 125 of the housing 12, so that the ferrite sheet 18 provides an electromagnetically isolating sheet between the SIM card and the metal parts of the cell phone.

The SIM card holder 10 can advantageously be used with any SIM card having dual functionalities of RFID and smart card. Indeed, the ferrite sheet 18 of the SIM card holder 10 reduces the interference between the radio waves transmitted by such a SIM card and the metal parts of a

cell phone, preventing the decrease of the contactless communication distance.

According to one embodiment of the invention, one or more of the carrier 30, the substrate 28 or the protective sheet 26 comprises a ferrite material.

For example, the substrate 28 is made of a ferrite material .

Fig. 3 and 4 show, in a more detailed manner, a substrate 28 according to an embodiment of the invention. The substrate 28 comprises on its top main face 281 a SIM card contact area 32. The SIM card contact area 32 comprises a plurality of contacts 38, each of the contacts 38 is rectangularly shaped and the SIM card contact area 32 forms a rectangular footprint. The substrate 28 also comprises an antenna area 34. The antenna area 34 comprises an antenna 40 with a number of turns suitable for contactless communication with a suitable contactless complementary device with a range for instance of at least four centimetres. For example, the turns are disposed on the top main face 281 of the substrate 28 receiving the contacts, or on the bottom main face 282. In order to integrate even more turns in a substrate of a size as low as the size of a SIM format card, the antenna 40 can be provided, as in the embodiment shown on Fig. 3 and 4, in the form of a first loop 401 on the top main face 281 of the substrate 28 which receives the contacts 38, and a second loop 402 provided on the bottom main face 282.

The first loop 401 is mainly provided side by side with the contacts 38, and wires 42 extend from the first loop 401 to be connected to some of the contacts 38. Possibly, some turns are provided around the contacts 38 for increasing the length of the antenna 40. As shown, the

second loop 402 is directly opposite to the first loop 401.

Some turns of the second loop 402 may also extend around a chip (48 on Fig. 5) . The two loops 401 and 402 are electrically connected together through metallised holes 44 extending through the substrate 28.

As shown on Fig. 5, connecting features 46 are provided on the bottom main face 282 of the substrate 28 for connection of a chip 48 according to well known methods . The substrate as shown on Fig. 3, 4 and 5, with its integrated chip 48, can be readily integrated into a SIM

(Subscriber Identity Module) format card by injection moulding between two plastic sheets (26,30) . The obtained

SIM card 24 can be readily inserted into a mobile phone comprising a card reader comprising terminals contacting the contacts 38 of the SIM card 24 for enabling use of the mobile phone. Further, the mobile phone comprising the SIM card 24 of the invention will provide contactless communication to some adapted contactless complementary tags external to the phone through the antenna 40 provided on the SIM card 24.

Advantageously, the SIM card 24 can be used with any card having dual functionalities of RFID and smart card. Indeed, the ferrite sheet 18 of the SIM card holder 10 or/and of the SIM card 24 itself reduces the interference between the radio waves transmitted by such a SIM card and the metal parts of a cell phone, preventing the decrease of the contactless communication distance.

Although, the present invention has been described with reference to preferred embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the scope of the invention.