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:
Nov. 21, 2000
Filed:
Jan. 29, 1999
Louis R Nerone, Brecksville, OH (US);
David J Kachmarik, Strongsville, OH (US);
General Electric Company, Schenectady, NY (US);
Abstract
A ballast circuit for a gas discharge lamp with a tapless feedback circuit is disclosed. The ballast circuit comprises a d.c.-to-a.c. converter circuit with circuitry for coupling to a resonant load circuit, for inducing a.c. current therein. The converter circuit comprises a pair of switches serially connected between a bus conductor at a d.c. voltage and a reference conductor. The voltage between a reference node and a control node of each switch determines the conduction state of the associated switch. The respective reference nodes of the switches are connected together at a common node through which the a.c. current flows, and the respective control nodes of the switches are connected together. A gate drive arrangement regeneratively controls the first and second switches. It comprises a coupling circuit including an inductor for coupling to the control nodes a feedback signal representing current in the load circuit. It further comprises a tapless feedback circuit for providing the feedback signal. The feedback circuit comprises a capacitor coupled at one end to the common node in such manner as to conduct load current, and coupled at another end to the inductor.