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:
May. 09, 2006
Filed:
Jun. 03, 2004
Jun Nagai, Hino, JP;
Hitoshi Tsuji, Machida, JP;
Jun Nagai, Hino, JP;
Hitoshi Tsuji, Machida, JP;
Murata Manufacturing Co., Ltd., Kyoto, JP;
Abstract
A switching electric source device includes a first synchronous rectifier control circuit, which detects the resonance state developed based on the exciting energy of the primary winding after the main switching element switches off, and causes a first synchronous rectifier to switch on earlier during the time period from the completion of the resonance state to the switching on of the main switching element. Thus, the first synchronous rectifier switches on during the time period, and thus, current is prevented from flowing through a body diode, so that a voltage caused by the voltage drop in the body diode is prevented from being induced in the secondary winding and the third winding. As a result, variations in the output voltage, which is caused by the induced voltage of the third winding, can be prevented. The output voltage can be stabilized.