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:
Apr. 18, 2000
Filed:
Aug. 03, 1998
Marcel J Bucks, Eindhoven, NL;
Engbert B Nijhof, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A circuit arrangement for driving a light source includes input terminals (T1, T2) for deriving a supply current from a supply source; a circuit I for generating a control signal S; a circuit II, provided with a converter which is fitted with at least one switching element (13) and with a control circuit (17) which triggers the switching element with high frequency in a manner which is dependent on the value of the control signal S; a circuit III for generating a voltage Sc which is a measure for an instantaneous value of a supply voltage delivered by the supply source, the voltage Sc acting as a reference signal which causes the circuit I to generate a control signal S which lies alternately in a first range and in a second range, and the circuit II causing the drawing of a comparatively strong supply current (Iv1) at a value of the control signal S which lies in the first range, and the drawing of a comparatively weak supply current (Iv2) at a value of the control signal S which lies in the second range; and output terminals (T3, T4) coupled to the circuit II for connection to a light source (LI).