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. 13, 2018
Filed:
Jul. 10, 2017
Dialog Semiconductor Inc., Campbell, CA (US);
Chenglong Zhang, Campbell, CA (US);
Nan Shi, Campbell, CA (US);
DIALOG SEMICONDUCTOR INC., Campbell, CA (US);
Abstract
Systems, devices, and methods for dimming of solid state lighting reduce ripple and flicker at low load dimming levels (low LED current, lower light levels) yet provide full power to the load at high load dimming levels (high LED current, higher light levels) thereby reducing power loss compared to conventional dimming techniques. When dimming to lower light levels a flicker resisting metal oxide semiconductor field effect transistor (MOSFET) connected to the LED operates in linear mode such that the relationship of its drain-source voltage to the LED current is resistive to provide flicker reduction. Conversely, at higher light levels the flicker resisting MOSFET is operated in saturation mode such that full power is supplied to the LED as flicker reduction is less needed. The disclosed techniques also reduce undershoot and overshoot of the LED voltage during transitions in dimming control from high to low and low to high respectively.