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:
Jul. 05, 2016
Filed:
Dec. 25, 2012
Sichuan Sunfor Light Co., Ltd., Chengdu, Sichuan, CN;
Dongming Li, Sichuan, CN;
Mian Yang, Sichuan, CN;
Zhengyong Feng, Sichuan, CN;
Wentao Long, Sichuan, CN;
Kun Zhao, Sichuan, CN;
Ming Zhang, Sichuan, CN;
SICHUAN SUNFOR LIGHT CO., LTD., Sichuan, CN;
Abstract
The present invention discloses a white LED light emitting device driven directly by constant current in manner of being supplied with alternating current. N parallel branches, consisting of LED modules and constant current units which are in series connection with the LED modules, are connected to an output terminal of a rectification circuit, and by setting the current value, the turning-off voltage, and the turning-on voltage of the constant current unit of each branch, the periodic flickers generated due to changes in the voltage of the alternating current can be avoided. Because the current of each branch is constant, the changes in junction temperatures do not result in the current changing in LED, and the reliability is improved. Along with the increase of the number of the branches, the driving current waveform approximates a sine wave, and the power factor and the efficiency of the light emitting device are improved.