SERIES REGULATOR POWER SUPPLY CIRCUIT

摘要

PROBLEM TO BE SOLVED: To improve the removing ratio of ripples included in the power supply voltage of a series regulator power supply circuit to be used as a power supply for electronic equipment or the like. SOLUTION: The MO of a PMOS FET is used as an output, and the intermediate voltage between resistors R1, R2 connected between the PMOS FET and ground is compared with a reference voltage applied from a reference voltage circuit 2 and the output stage 3 of an amplifier circuit 1 using input power supply VIN or an output as a power supply (terminal 5) is provided with a constant current source with a filter in order to control the MO by the circuit 1 and output required output voltage. Thus the removing ratio of ripples can be improved by allowing high frequency ripples included in the power supply (terminal 5) of the circuit 1 to pass the output.