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:
Jan. 26, 2016
Filed:
Jan. 22, 2013
Bernhard Siessegger, Danvers, MA (US);
Marijan Kostrun, Newbury, MA (US);
Bernhard Siessegger, Danvers, MA (US);
Marijan Kostrun, Newbury, MA (US);
OSRAM SYLVANIA INC., Wilmington, MA (US);
Abstract
Solid state lighting systems are disclosed for providing uniform brightness of LEDs serially connected in a string. In some embodiments, the LEDs can be powered directly from the mains such that no switch-mode power supply or the output storage elements associated therewith are needed. In some such cases, a linear regulator and switches can be used to control the current through the LEDs to provide uniform brightness. Other embodiments can be used with a switch-mode based driver topology and/or storage elements coupled in parallel with clusters of the LEDs. In any such cases, control logic (e.g., microcontroller or other suitable controller) can be used to control the switches accordingly to provide uniform brightness, and in some cases, to mitigate the implications of having no SMPS output storage element. In some embodiments, the switching pattern provided by the control logic is random, although other switching patterns can be used.