| 摘要 |
<p>A noncontact IC card where a driver (5) switches the resonance frequency of a resonance circuit (1) in order, a reference voltage generator (6) receives the output voltage of the resonance circuit (1) and outputs a certain reference voltage, an output value measurer (7) measures the magnitude of the output voltage of the resonance circuit (1) at each resonance frequency, with this reference voltage as a reference, an output value storage (8) stores the measurement value (output value), and a mode determiner (9) selects the largest one out of the output values stored in the output value storage (8) and determines the switching mode corresponding to this as an appropriate switching mode. In this way, the noncontact IC card is provided with the appropriate switching mode in which it can receive power supply most efficiently.</p> |
