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:
Dec. 21, 1999
Filed:
Oct. 16, 1998
Nortel Networks Corporation, Montreal, CA;
Concordia University, Montreal, CA;
Abstract
A flyback converter has a main switch coupling a primary winding of a transformer between supply terminals, a duty cycle of the main switch controlling an output of the converter derived from a secondary winding of the transformer. Soft (zero voltage) switching of the main switch is facilitated by a snubber capacitor in parallel with the main switch. An auxiliary circuit coupled in parallel with the snubber capacitor and main switch includes a series-connected auxiliary switch, capacitor, and inductor coupled via another inductor to a full wave rectifier arrangement for recovering energy from the snubber capacitor. Resonant circuits provided by the auxiliary circuit facilitate soft switching of the auxiliary switch for low power loss and high frequency operation. The switches can be MOSFETs with reverse-poled diodes in parallel with their drain-source paths.