SEMICONDUCTOR DEVICE AND IC LABEL, IC TAG, AND IC CARD PROVIDED WITH SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To solve the problem wherein it takes a long time to obtain a desired voltage in accordance with the time for accumulating charges in a capacitor when increasing electrostatic capacitance of the capacitor in order to supply a stable voltage, and it becomes difficult to accumulate inputted charges and to apply a stable voltage to a constant voltage circuit of the next stage when reducing the electrostatic capacitance of the capacitor, while a desired voltage is obtained.

SOLUTION: There is provided a charge accumulation circuit having a structure in which a capacitor is divided into a plurality of pieces and the divided capacitors are connected in parallel through switches. The charge accumulation circuit controls the switch provided between the capacitors, and thus dynamically varies electrostatic capacitance of the charge accumulation circuit which applies a voltage to a constant voltage circuit.

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