POWER SUPPLY DEVICE

There is provided a power supply device configured to boost an input voltage to output an output voltage, the power supply device including: an oscillator circuit configured to receive the input voltage and to output an oscillation signal; a step-up circuit configured to output a boost voltage based on the oscillation signal; a first hysteresis comparator and a second hysteresis comparator configured to compare boost voltages with threshold values; a first switch that is connected between the oscillator circuit and the step-up circuit and that is controlled based on a comparison result of the first hysteresis comparator; and a second switch that is connected to an output terminal configured to output the output voltage and that is controlled based on a comparison result of the second hysteresis comparator.