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:
Jul. 02, 1991
Filed:
Jun. 20, 1990
Ronald A Lesea, Redwood City, CA (US);
GTE Products Corporation, Danvers, MA (US);
Abstract
A single-ended ballast circuit employs a power-factor-correcting network (510); a DC power supply (512); a free-running oscillator (516); a transistor (518); a current-limiting (ballasting) network (520); and two fluorescent lamps (524). The transistor (518) is configured as a switch connected to be responsive to a signal generated (630) by the oscillator (516) and operative to periodically couple a line (734) to a circuit common. The current-limiting (ballasting) network (520) includes an inductor or transformer (740) having a primary winding (744), connected between a DC power-supply potential and the line (734), and a secondary winding (746); a first capacitor (750), connected between the line (734) and circuit common; an inductor (752); a second capacitor (756), connected in series with the inductor (752) across the secondary winding (746); and a third capacitor (754), connected in series with the lamps (524) across the second capacitor (756).