| 摘要 |
PROBLEM TO BE SOLVED: To stabilize the action of a non-contact IC card and to improve its reliability without bringing about its capability deterioration. SOLUTION: This non-contact IC card ICC which is provided with a card side antenna ANTC that is electromagnetically coupling with a reader/writer side antenna ANTR, a capacity means which is provided parallel with the antenna ANTC and constitutes a tuning circuit for a carrier together with the antenna ANTC and a bridge circuit BRGC which rectifies the carrier and generates a DC power supply voltage VCC and receives the supply of operation power by electromagnetic coupling, is provided with a plurality of capacities C1 to C3 which, e.g. are parallelly connected as the capacity means, receive the effective levels of corresponding voltage control signals CS1 to CS3 and are selectively made effective and also a power supply voltage control circuit VC which monitors the voltage VCC and selectively makes the signals CS1 to CS3 an effective level in accordance with its electric potential. |
