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:
Apr. 21, 2009
Filed:
Apr. 21, 2005
Syohei Osaka, Niiza, JP;
Syohei Osaka, Niiza, JP;
Sanken Electric Co., Ltd., Niiza-shi, JP;
Abstract
A switching power supply that can accurately detect a period during energy is supplied from a primary side to a secondary side of a transformer with a simple circuit configuration is provided. A first switching element and a second switching element are serially connected to opposite output ends of a full-wave rectifier rectifying an AC voltage from an AC power source. A current resonant capacitor, a resonant reactor, and a primary winding of a resonant transformer are serially connected to opposite ends of the first switching element. A rectifying and smoothing circuit rectifies and smoothes a voltage of a secondary winding, a control circuit alternately turning on and off the first switching element and the second switching element based on an output voltage of the rectifying and smoothing circuit, and a resonant period detection circuit detects a period, during which energy is transmitted from a primary side to a secondary side, based on a voltage of an auxiliary winding tightly coupled with the secondary winding, and outputs a resonant period detection signal.