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. 24, 1991
Filed:
Nov. 16, 1990
Bernardus J Overgoor, Eindhoven, NL;
Johannes M Van Meurs, Eindhoven, NL;
Marcel Beij, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
The invention relates to a circuit arrangement for operating a discharge lamp, comprising a DC-AC converter provided with a switching element for generating a current whose polarity changes with a frequency f, a current sensor (SE), a drive circuit (III) for generating a drive signal to make the switching elements alternately conducting with the frequency f, a measuring circuit (I) coupled to the current sensor and having at least one switching element for generating a control signal which is dependent on a phase difference between a voltage across the load circuit B and a current through the load circuit B and on a second signal which is a measure for a minimum required phase difference, and a control circuit (II) for effecting a change in an operating condition of the DC-AC converter, this change being dependent on the control signal.