| 摘要 |
PROBLEM TO BE SOLVED: To provide a power control circuit in simple structure and an electronic device which can reduce the power consumption of an electronic device equipped with an automatic power-off function when its power source is turned off and which does not employ a microcomputer. SOLUTION: When a power switch SW3 is turned on, 1st and 2nd transistors Q3 and Q2 turn on which electric charges accumulated in a capacitance element C1 in the OFF period of the power switch SW3, and a battery BATT3 supplies electric power to a timer circuit 57 and a circuit block 54 through the 2nd transistor Q2. The timer circuit 57 once supplied with the electric power discharges the electric charges charged up in the capacitance element C1 to keep the 1st transistor Q3 on before the 1st transistor turns off, then measures a specific fixed time according to the output signal of the circuit block 54, and turns off the 1st transistor Q3 when detecting the circuit block 54 not in operation for the specific fixed time.
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