摘要 |
PURPOSE: An electric charge storage circuit is provided to reduce stand-by current by controlling period of signal oscillated in low voltage oscillator. CONSTITUTION: A low voltage oscillator(21) oscillates a signal of an appointed period. A clock generator(22) is driven according to the output signal of the low voltage oscillator(21) and an output signal of a comparator(27). The comparator(27) compares a voltage distributed in a voltage distributor(25) with a voltage generated in a reference voltage generator(26) and determines an output signal, and outputs a signal for driving the clock generator(22) in case electric charge quantity accumulated in a capacitor(CR) is less than an appointed value. A pump circuit(23) is driven by a clock generated in the clock generator(22) and pumps voltage to a degree of appointed potential. The capacitor(CR) accumulates electric charge according to the pumped voltage.
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