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:
Nov. 09, 2010
Filed:
Jun. 13, 2007
Xi Yuan He, Guangzhou, CN;
Rui MA, Guangzhou, CN;
Giovanni Scilla, Fontane di Villorba, IT;
OSRAM Gesellschaft mit beschraenkter Haftung, Munich, DE;
Abstract
A driver arrangement for LED light sources includes a transformer having primary and secondary winding connections. A first electronic switch (SW) controls current flow through the primary winding, and a sensing resistor is coupled to the primary winding to produce a current sensing signal. A second electronic switch (SW) is sensitive to the sensing signal to switch off SWas current flow through the primary winding reaches a given threshold. SWis thus alternatively turned-on and off in alternating turn-on and switch-off phases to power the LED light source via the secondary winding. SWis a field effect transistor, preferably a MOSFET. The transformer is SELV-rated. The sensing resistor may be a variable resistor to adjust the duration of the on/off phases to permit controlled dimming.