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:
Aug. 23, 2011
Filed:
Dec. 12, 2006
Josephus Adrianus Maria Van Erp, Eindhoven, NL;
Josephus Adrianus Maria Van Erp, Eindhoven, NL;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
The present invention relates to a multiple LED driver circuit in which each LED () is controlled by a bypass switch (). The LEDs are supplied by a switched mode power supply () and are connected to a constant current source to draw a predetermined current through the LEDs. The switched mode power supply is arranged to output different voltages depending on the number of switched-on LEDs. This is carried out by supplying the control signals (sw, sw) of the bypass switches to the switched mode power supply. In this way, the power dissipation of the constant current source can be kept at a low level.