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:
Oct. 21, 2014
Filed:
Dec. 09, 2010
Xinke Wu, Hangzhou, CN;
Liang'an GE, Hangzhou, CN;
Xinke Wu, Hangzhou, CN;
Liang'an Ge, Hangzhou, CN;
Inventronics (Hangzhou) Co., Ltd., Hangzhou, Zhejiang, CN;
Abstract
A drive circuit for realizing accurate constant current of multiple LEDs is disclosed. The drive circuit comprises a high-frequency impulse Alternating Current (AC) power carrying N circuit units with same structure. Each of the circuit unit comprises a rectifier filter circuit, a blocking capacitor Cand two LED loads. The rectifier filter circuit comprises two independent half-wave rectifier circuits, and two filter capacitors. Each of the two half-wave rectifier circuits comprises two diodes connected in series to supply power for the corresponding LED load. The filter capacitor is connected in parallel with the two ends of an LED load respectively, and the blocking capacitor Cis connected in series with the input end of the rectifier filter circuit. The circuit also comprises N−1 equalizing transformers, each of which connects in series between two adjacent circuit units. A drive circuit for constant output current of multiple LEDs with high efficient, low cost and great flow equalization is provided in the embodiment of the invention. When the differential voltage of the two LED loads is large, high efficiency can also be achieved.