Patent Number: 6,294,903

Title: Switching power supply

Abstract: A switching power supply of a step-down chopper system, which is capable of reducing power consumption and unused power supply to the output. A voltage supplied to an input main terminal is turned ON/OFF by a switching device controlled by a control circuit, and outputted to an output main terminal through a conversion circuit. An output voltage detecting circuit detects the output voltage at the output main terminal, and according to the state of the output voltage detected, a feedback circuit is controlled, so that the ON/OFF control over the switching device by the control circuit is paused (or stopped). Thus, the switching device oscillates or is paused (stopped) according to the output voltage.

Inventors: Yamashita; Tetsuji (Osaka, JP), Mori; Yoshihiro (Kyoto, JP), Yamanishi; Yuji (Osaka, JP), Hachiya; Yoshiaki (Shiga, JP)

Assignee: Matsushita Electric Industrial Co., Ltd.

International Classification: H02M 3/04 (20060101); H02M 3/156 (20060101); G05F 001/40 (); H02M 005/42 ()

Expiration Date: 09/25/2018