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:
Oct. 13, 2015
Filed:
Sep. 13, 2013
Applicant:
Nxp B. V., Eindhoven, NL;
Inventors:
Assignee:
NXP, B.V., Eindhoven, NL;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01R 31/00 (2006.01); G01R 31/08 (2006.01); H05B 33/08 (2006.01); G01R 31/26 (2014.01);
U.S. Cl.
CPC ...
H05B 33/0884 (2013.01); G01R 31/2635 (2013.01); H05B 33/089 (2013.01); H05B 33/0893 (2013.01);
Abstract
Disclosed herein is a method of detecting an LED failure in a series-connected string of LEDs using a parameter indicative of a voltage difference between a voltage across the string at a predetermined relatively high current and a voltage across the string at a predetermined relatively low current. The disclosure extends to controllers configured to detect an LED failure in a string of LEDs, to LED lighting units comprising such controllers, and to lighting subsystems, for instance automobile lighting subsystems.