Patent ID: 7573247

Claim:
A series regulator circuit comprising: a first transistor connected to a constant current source, which is connected to an input voltage line, and a reference voltage line; a second transistor connected to the input voltage line and an output terminal; a first resistor, second resistor, and third resistor connected in series between the output terminal and the reference voltage line; a third transistor connected between the input voltage line and a connection node of the first and second resistors, wherein, the first transistor has a control terminal connected between the second resistor and the third resistor; and the second and third transistors each have a control terminal connected to a first connection node between the constant current source and the first transistor; a capacitor connected to the control terminals of the second and third transistors, and the reference voltage line; a fourth transistor connected to the reference voltage line and the output terminal; and a fifth transistor connected to the reference voltage line and a connected node of the first and second resistor, wherein the fourth and fifth transistors each have a control terminal connected to a second connection node between the constant current source and the first transistor.