Patent ID: 8872490

Claim:
A voltage regulator, comprising: a constant voltage generation circuit for generating a reference voltage; an amplifier for amplifying and outputting a difference between the reference voltage and a divided voltage obtained by dividing an output voltage output from an output transistor, and controlling a gate of the output transistor; an external terminal for inputting a signal for turning ON and OFF a circuit from outside; and a start-up circuit for starting the constant voltage generation circuit, the start-up circuit comprising: a constant current circuit; a first transistor connected between the constant current circuit and the constant voltage generation circuit; a second transistor including a drain connected to a gate of the first transistor, and a gate to which a voltage based on the output voltage is input; a first depletion transistor including a gate connected to the drain of the second transistor, and a source connected to a source of the second transistor; and a third transistor including a gate connected to the gate of the second transistor, and a drain connected to the drain of the second transistor.