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:
Mar. 12, 2013
Filed:
Aug. 26, 2010
Mark Jutras, Upton, MA (US);
Mark Masera, North Grafton, MA (US);
Scott Moore, Westford, MA (US);
Bel Fuse (Macao Commercial Offshore), Andar H-K, MO;
Abstract
A power supply for an LED lamp has a set of coupled coils, primary-side power circuitry including a converter power switch for conducting input power, and secondary-side power circuitry including a dimming power switch. Power control circuitry includes converter control circuitry which generates a converter control signal for the converter power switch to maintain a desired undimmed level of lamp current at a normal operating value of a lamp voltage. Dimming control circuitry generates a dimming control signal for the dimming power switch to pulse-width modulate the lamp current at a duty cycle corresponding to a desired dimming. Operation of the converter control circuitry is modified during dimming to prevent an automatic increase of the lamp voltage in response to a decrease in lamp current, avoiding undesirable overshooting of the lamp current and providing more accurate and effective control over dimming operation.