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:
Sep. 05, 1995
Filed:
Aug. 25, 1993
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A switching power supply supplies a regulated output voltage and suppresses spike voltage and spike current generated by a switching action of transformers, and suppresses switching frequency drift due to load variation. Output stability of multi-output design is improved and recovery of rectifying diodes by a current resonance are suppressed. A reduction of noise interference to electronic equipments and power loss in the switching power supply itself results. A series connection of a primary winding of a first transformer and a first switching means, which repeats an on/off action is connected across a d-c power source. A series connection of a second switching means, which repeats an on/off action alternately with the first switching means, and a first capacitor is connected in parallel with the primary winding of the first transformer. A series connection of a primary winding of the second transformer and a second capacitor is connected in parallel with the second switching means. Regulated d-c outputs are taken out from each secondary winding of the transformers through rectifiers/filters. A control circuit supplies on/off signals, which on/off-ratios are varied according to one of the regulated d-c outputs, to the first and the second switching means.