A power supply circuit is disclosed. The power supply circuit is provided with a reference voltage generation circuit to receive a voltage from a higher voltage supply so as to generate a reference voltage. The reference voltage from the reference voltage generation circuit is outputted to a power supply voltage generation circuit. The power supply voltage generation circuit boosts the reference voltage to generate a boosted power supply voltage. The boosted power supply voltage is inputted to a bandgap reference circuit. The bandgap reference circuit generates a reference voltage by using the boosted power supply voltage.