Title:
USB COMPATIBLE SPEAKER DRIVE SYSTEM
Document Type and Number:
Japanese Patent JP3457596
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To drive a speaker without relying on an exclusive power supply by supplying power to a speaker drive amplifier via a USB port.
SOLUTION: The speaker drive system is provided with speaker drive amplifiers 17L (noninverting amplifier) and 17R (inverting amplifier) that are operated by power supplied via the USB port 12a and high efficiency speakers 18L and 18R driven by the speaker drive amplifiers 17L and 17R to supply power to the speaker drive amplifiers 17L and 17R via the USB standard interface. Sufficient sound reproduction is attained by combining the high efficiency speakers 18L and 18R of e.g. 87-90 dB/W with the speaker drive amplifiers 17L and 17R whose maximum current consumption is 0.1 ampere or below under the restriction of the USB bus power of DC 5 V and 0.1 ampere.
Inventors:
Naka Masamura
Kento Castle
Kento Castle
Application Number:
JP32935499A
Publication Date:
October 20, 2003
Filing Date:
November 19, 1999
Export Citation:
Assignee:
NEC View Technologies, Ltd.
International Classes:
G06F1/18; H03F3/181; H03F3/68; H04R3/00; (IPC1-7): H04R3/00; G06F1/18; H03F3/181; H03F3/68
Domestic Patent References:
| JP1127776A | ||||
| JP2188100A | ||||
| JP1051888A | ||||
| JP7111698A |
Attorney, Agent or Firm:
Johei Yamashita