| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for suppressing the temperature rise of a contactless IC card. SOLUTION: If the temperature of an IC chip 110 is below a predetermined level, a resonance circuit comprising an antenna coil 101 and a tuning capacitor 111, capacitors 112 and 113 lie in non-contact state. If the temperature of the IC chip 110 exceeds the predetermined level, the capacitors 112 and 113 are connected in parallel to the resonance circuit comprising the antenna coil 101 and the tuning capacitor 111, thereby reducing a received power, allowing the temperature of the IC chip 110 to be suppressed to prevent the distortion of a card caused by heat, the deterioration of operating characteristics of breakage of a semiconductor device inside the circuit or the like. |
