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:
Oct. 23, 2007
Filed:
Sep. 13, 2005
Masayuki Yasumura, Kanagawa, JP;
Masayuki Yasumura, Kanagawa, JP;
Sony Corporation, , JP;
Abstract
A secondary side series resonant circuit formed by at least one secondary winding and a secondary side series resonant capacitor is provided together with a secondary side series resonant circuit forming a current resonant converter, whereby a coupling type resonant circuit is formed by magnetic coupling of an isolated converter transformer. For this coupling type resonant circuit to obtain a unimodal characteristic, a gap G formed in a core of the isolated converter transformer PIT is set to about 2.4 mm, and a coupling coefficient k is set to k=0.65 or lower. Thereby, the variable control range of switching frequency can be reduced, and a wide range-ready configuration can be realized. Also, since the variable control range of the switching frequency can be thus reduced, cross regulation of secondary side direct-current output voltage −Eo can be improved.