Abstract: The present invention provides a clock signal generator capable of reducing current consumption and stably outputting a clock signal early. When it is discriminated that the amplitude of an amplification oscillation signal obtained by amplifying an oscillation signal produced from a crystal oscillator according to a constant current value has exceeded threshold amplitude, the clock signal generator generates a clock signal, based on the amplification oscillation signal. When it is discriminated that the total number of clock pulses of the clock signal has exceeded a predetermined pulse number, the clock signal generator reduces the constant current value.

Abstract: The present invention provides a clock signal generator capable of reducing current consumption and stably outputting a clock signal early. When it is discriminated that the amplitude of an amplification oscillation signal obtained by amplifying an oscillation signal produced from a crystal oscillator according to a constant current value has exceeded threshold amplitude, the clock signal generator generates a clock signal, based on the amplification oscillation signal. When it is discriminated that the total number of clock pulses of the clock signal has exceeded a predetermined pulse number, the clock signal generator reduces the constant current value.