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:
Feb. 02, 1999
Filed:
Jul. 07, 1997
Machiel A Hendrix, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A circuit arrangement for operating a discharge lamp. Input terminals are coupled to the poles of a supply voltage source which delivers a low frequency supply voltage. A rectifier is coupled to the input terminals for rectifying the low frequency supply voltage. A branch interconnects output terminals of the rectifier and includes a series arrangement of a first diode, a second diode, and a third diode. The first and second diodes are shunted by a first capacitor. The second and third diodes are shunted by a second capacitor. A resistor passes current during lamp operation with which the first and second capacitors are charged. Lamp current is generated based on the voltages across the first and second capacitors. The resistor is placed in a branch which passes a low frequency alternating current during lamp operation and which connects an input terminal to an input of the rectifier. The circuit arrangement has a high power factor. Radio frequency interference generated in producing the lamp current is effectively suppressed.