Patent ID: 7956588

Claim:
A voltage regulator, comprising: an error amplifier circuit that amplifies and outputs a difference between a reference voltage and a voltage based on an output voltage of an output transistor to control a gate of the output transistor; and a phase compensation circuit that is disposed between the output transistor and the error amplifier circuit and that compensates a phase of an output signal of the error amplifier circuit, wherein the phase compensation circuit includes a phase compensation resistor and a phase compensation capacitor, wherein the phase compensation resistor comprises: a first phase compensation resistor having one terminal connected to an input terminal of the phase compensation circuit; a second phase compensation resistor having one terminal connected to another terminal of the first phase compensation resistor, and another terminal connected to an output terminal of the phase compensation circuit; and a control transistor having a source connected to the input terminal of the phase compensation circuit, a drain connected to the output terminal of the phase compensation circuit, and a gate connected to the another terminal of the first phase compensation resistor and the one terminal of the second phase compensation resistor; and wherein a resistance of the phase compensation circuit decreases in a transient state in which the output signal of the error amplifier circuit changes.