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:
Apr. 07, 2020
Filed:
Sep. 05, 2019
Jie Dong Wang, Irvine, CA (US);
Jie Dong Wang, Irvine, CA (US);
DMF. Inc., Carson, CA (US);
Abstract
Light output from an LED light source is increased or reduced in response to adjustment of a triac-based dimmer having a triac holding current to maintain conduction of the dimmer. An LED controller to control the light output includes a voltage-controlled impedance to provide an adaptive holding current that causes a triac current of the dimmer to be greater than the triac holding current, particularly when the dimmer is adjusted for significantly low light output (e.g., less than 5%, 2%, or 1% of full power light output). The adaptive holding current also allows for smooth increase of the light output starting from low light output, without perceivable flicker or shimmer. In one example, the voltage-controlled impedance is a resistive-like impedance that is placed on a secondary side of a transformer providing power to the LED light source. In another example, the voltage-controlled impedance is not pulse width modulated.