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. 02, 1995
Filed:
Oct. 15, 1993
Hiroshi Uramoto, Hadano, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
The present invention is an ON/OFF type self-oscillating DC--DC converter with zero voltage switching and is provided with a transformer, a switching element on the primary side and a diode on the secondary side of the transformer, and configured so that the current (signal) flowing in the secondary side is detected by a resistor. The detected current is delayed by a comparator and provided with a short circuit which shorts the diode driven by the delayed signal. The present invention uses this arrangement to perform a switching operation at zero volts so that there is no switching loss, to improve the conversion efficiency and to have stable transmission operation even for non-load operation.