To provide a driving circuit for a charge pump reduced in noise by reducing unnecessary electric power consumption.
The driving circuit 1A for a charge pump is adapted as follows. In a driving circuit for a charge pump including an FETQ, a charge pump for charging a gate of the FETQ with electricity, and an oscillation circuit 5 for generating a clock signal and hereby driving the charge pump 3 following the clock signal, there are provided a differential amplifier 7 for detecting voltage of the gate of the FETQ, and a comparator 9 for interrupting the oscillation circuit 5 to stop the charging for the gate of the FETQ when the gate voltage of the FETQ detected by the differential amplifier 7 exceeds predetermined voltage beyond on-voltage, while charging the gate of the FETQ with electricity by driving the oscillation circuit 5 when the gate voltage of the FETQ lowers to the predetermined voltage or lower.
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