Patent ID: 7091709
Filing Date: 2006-08-15
Classification: G05F

Abstract:
1. A constant voltage power supply circuit comprising: a differential-operation type amplifier of which a first input terminal is supplied with a reference signal, and of which a second input terminal is supplied with a feedback signal, said amplifier outputting a first control signal responsive to a difference between the reference signal and the feedback signal; an output transistor a output voltage detection circuit detecting an output voltage of the output transistor and applying a voltage corresponding to the detected voltage as the feedback signal to the second input terminal of the amplifier; a first capacitor of which one end is connected to the output the output transistor; and a first control circuit, of which a first input terminal is connected to a first output terminal of the amplifier, of which a second input terminal is connected to another end of the first capacitor and of which an output terminal is connected to a control input terminal of the output transistor, said first control circuit generating a second control signal in response to the first control signal output from the amplifier and an output signal of the first capacitor and supplying the resultant second control signal to the control input terminal of the output transistor.