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. 29, 1987
Filed:
Sep. 22, 1986
Raoji Patel, Framingham, MA (US);
Unitrode Corporation, Lexington, MA (US);
Abstract
A synchronous power rectifier incorporating a bipolar power transistor operable in a switching mode to rectify the energy from a secondary winding of a power transformer. The synchronous rectifier reduces or eliminates the need of rectifier diodes, which provides power rectification without the power loss associated with the rectifier diode voltage drops. Moreover, the present invention includes further refinements of the circuit, including adjustment of the rectifier switching time to accommodate delayed turn-off times of bipolar power devices, and adjustment of the switching signal duration to provide output voltage regulation independent of the excitation of the transformer primary. The resulting embodiments of the present invention provide a modular switching power supply circuit of high efficiency, which may be operable together in combination to provide multiple output voltages.