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Title:
CONTACTLESS IC CARD READER/WRITER DEVICE
Document Type and Number:
Japanese Patent JP3935002
Kind Code:
B2
Abstract:

PROBLEM TO BE SOLVED: To reduce the power consumption of a contactless IC card reader/writer device.
SOLUTION: The IC card reader/writer 1 has in a power source part 16 constant current circuits 163 and 164 capable of outputting constant currents of I1A and I2A, respectively. When an IC card of high power consumption or two IC cards are inserted, a control part 11 switches the constant current circuit 164 on with a control signal CNT to output the constant current I2A and supply a constant current amounting to (I1 + I2)A including the constant current I1A of the constant current circuit 163 normally in an ON state to a driver 12C in a modulation circuit 12, which transmits a modulated signal to the IC card(s), and when an IC card of low power consumption or one IC card is inserted, the control part switches the constant current circuit 164 off to supply only the constant current I1A of the constant current circuit 163 to the driver 12C, which transmits a modulated signal to the IC card.


Inventors:
Takashi Nishikawa
Toyohiko Akatsuka
Naofumi Suzuki
Akihiko Kasuya
Miura Toru
Application Number:
JP2002200170A
Publication Date:
June 20, 2007
Filing Date:
July 09, 2002
Export Citation:
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Assignee:
Saxa Co., Ltd.
Nippon Telegraph and Telephone Corporation
NTT Electronics Corporation
NEC TOKIN CORPORATION
International Classes:
B42D15/10; G06K17/00; G06F1/26; G06F1/32; (IPC1-7): G06K17/00; B42D15/10; G06F1/26; G06F1/32
Domestic Patent References:
JP11191146A
JP8191259A
JP2000194428A
JP1206366A
JP6260705A
JP2001143023A
JP10135884A
Attorney, Agent or Firm:
Masaki Yamakawa
Hiroro Kurokawa