The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 15, 2008
Filed:
Aug. 11, 2003
Koji Yoshida, Ikoma, JP;
Mitsuhiro Matsuo, Osaka, JP;
Satoshi Ikeda, Suita, JP;
Yoshihiro Takeshima, Nara, JP;
Koji Yoshida, Ikoma, JP;
Mitsuhiro Matsuo, Osaka, JP;
Satoshi Ikeda, Suita, JP;
Yoshihiro Takeshima, Nara, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A switching power supply comprises one or more switching sections which repeat ON/OFF operation, a transformer having a primary winding and a secondary winding, a synchronous rectifier section for rectifying a voltage induced in the secondary winding when an input voltage is applied to the primary winding of the transformer by the switching section, a smoothing section for smoothing the voltage rectified by the synchronous rectifier section to obtain an output voltage, a PWM control circuit which generates a PWM signal for adjusting the output voltage to determine an ON/OFF ratio of the switching section, and a drive transformer for ON-OFF driving the synchronous rectifier section according to the PWM signal, and is configured so as to use the energy stored in the drive transformer or the transformer for the ON/OFF operation of the synchronous rectifier section.