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. 08, 1987
Filed:
Jun. 25, 1986
Alan A Hoover, New Palestine, IN (US);
RCA Corporation, Princeton, NJ (US);
Abstract
In a switching power supply for a video display apparatus, the primary winding of an isolation power transformer is coupled to a chopper switch and to an AC mains rectified output voltage source. A control circuit regulates the conduction of the chopper switch. A B+ voltage for a horizontal deflection circuit is generated from a first secondary winding electrically isolated from the primary winding. An audio supply voltage for a power audio circuit is generated from a second secondary winding also electrically isolated from the primary winding. A first feedback winding, more tightly coupled magnetically to the first secondary winding, and a second feedback winding, more tightly coupled to the second secondary winding, develop respective feedback voltages. The feedback voltages are proportionally summed and applied to the control circuit to vary the conduction of the chopper switch in a manner that regulates the secondary winding voltages and stabilizes raster width with audio loading changes.