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:
May. 15, 2018
Filed:
Sep. 09, 2016
Nxp B.v., Eindhoven, NL;
Henricus Cornelis Johannes Büthker, Mierlo, NL;
Arnoud Pieter van der Wel, Vught, NL;
NXP B.V., Eindhoven, NL;
Abstract
Disclosed is a controller for controlling a string of N LEDs connected in series and each having a current bypass switch in parallel therewith and configured to be supplied from a current source connected in series with the string of LEDs and being supplied by a supply voltage, the controller comprising: a respective bypass switch controller for each bypass switch and configured to control the respective bypass switch such that the respective LED has an on-period and an off-period, according to a common duty cycle; a phase control unit configured to set a respective timing of each of the bypass switches such that the fraction of LEDs not bypassed corresponds to the duty cycle; and a duty cycle adjustor configured to adjust the duty cycle, in dependence on the supply voltage. Associated methods and circuits are also disclosed.