Patent ID: 9236792
Filing Date: 2016-01-12
CPC Classification: G05F,H02M

Claim Text:
1. A voltage regulator comprising: a reference voltage circuit which outputs a reference voltage; an output transistor; a differential amplifier circuit which amplifies and outputs a difference between the reference voltage and a divided voltage obtained by dividing an output voltage supplied from the output transistor and controls a gate of the output transistor; an inrush current protection circuit which controls a gate voltage of the output transistor to prevent an inrush current; and an output voltage detection circuit which controls the inrush current protection circuit, wherein the output voltage detection circuit comprises: a constant-current circuit having an input terminal thereof connected to a power supply terminal and an output terminal thereof connected to an output terminal of the output voltage detection circuit; a capacitor having one end thereof connected to the output terminal of the output voltage detection circuit and the other end thereof connected to a ground terminal; an amplifier, an inverting input terminal of which receives the divided voltage and a non-inverting input terminal of which receives the reference voltage; a first transistor, a source of which is connected to the power supply terminal, a gate of which is connected to the output terminal of the output voltage detection circuit, and a drain of which is connected to a power supply terminal of the amplifier; and a second transistor, a source of which is connected to the power supply terminal, a gate of which is connected to an output terminal of the amplifier, and a drain of which is connected to the output terminal of the output voltage detection circuit.