Patent ID: 7531996

Claim:
A low dropout regulator comprising: an input terminal, for receiving an input voltage; an output terminal, for outputting an output voltage from the input voltage after regulating; a N-type pass transistor, for supplying power from the input terminal to the output terminal, the N-type pass transistor having a drain terminal, a source terminal, and a gate terminal, wherein the drain terminal is coupled to the input terminal, and the source terminal is coupled to the output terminal; a P-type pass transistor, for supplying power from the input terminal to the output terminal, the P-type pass transistor having a drain terminal, a source terminal, and a gate terminal, wherein the source terminal is coupled to the input terminal, and the drain terminal is coupled to the output terminal; and a control circuit, for controlling the gate terminals of the N-type pass transistor and the P-type pass transistor to turn-one one of the N-type pass transistor and the P-type pass transistor to output the regulated voltage and to turn-off another of the N-type pass transistor and the P-type pass transistor; wherein the control circuit includes two error amplifiers, being used to control the N-type pass transistor for generating a first output voltage at the output terminal and to control the P-type pass transistor for generating a second output voltage at the output terminal.