A regulator includes a capacitor connected between a ground terminal and an output terminal at which a first voltage is supplied. The first voltage is higher than a power source voltage supplied to the regulator. A feedback circuit in the regulator is configured to output a boost signal corresponding to a comparison between the first voltage and a threshold voltage value. A clock generating circuit includes an oscillator circuit that outputs an oscillation signal and a buffer circuit that outputs a clock signal according to the oscillation signal. The clock signal has an electric current level that is controlled in accordance with the boost signal. A charge pump outputs the first voltage in accordance with the clock signal.