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:
Nov. 20, 2007
Filed:
Aug. 08, 2003
Masayuki Yasumura, Kanagawa, JP;
Masayuki Yasumura, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
A switching power supply circuit which can achieve enhancement of the power conversion efficiency is disclosed. In a composite resonance converter wherein a current resonance type converter constructed on the primary side and a primary side partial voltage resonance circuit are combined, a primary side DC input rectification circuit is formed from a full-wave rectification circuit. Further, a gap G of the core of an insulating converter transformer (PIT) is set to 2.0 mm to set the coupling coefficient of the primary winding (N) and the secondary winding (N) to approximately 0.81 of a loose coupling state. Further, the numbers of turns of the primary winding (N) and the secondary winding (N) are selected so that the induced voltage per one turn of the secondary winding (N) is 2 V or less. With the configuration, if the leakage inductance (L) of the primary winding (N) and the leakage inductance (L) of the secondary winding (N) are increased, then reduction of the primary side current (I) in a light load condition can be achieved and the switching output current (IQ), (IQ) can be reduced.