Patent ID: 6686728
Filing Date: 2004-02-03
Classification: G05F

Abstract:
A DC stabilized power supply circuit, comprising:a power transistor connected in series with a power supply line; a first difference amplifier in which an output voltage is stabilized by controlling a base current of said power transistor according to a difference between a feedback value of said output voltage and a predetermined first internal reference voltage so that said feedback value and said first internal reference voltage are equal to each other; a second difference amplifier in which a second internal reference voltage greater than said first internal reference voltage by a predetermined level is set, and the greater said feedback value of the output voltage is than said second internal reference voltage, the more said base current of the power transistor is restrained; and a third difference amplifier in which a third internal reference voltage smaller than said first internal reference voltage by a predetermined level is set, and the smaller said feedback value of the output voltage is than said third internal reference voltage, the more a gain of said first difference amplifier is increased.