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:
Dec. 25, 2012
Filed:
Apr. 16, 2010
Tiesheng Yan, Chengdu, CN;
Youling LI, Shenzhen, CN;
Feng Lin, Chengdu, CN;
Xinhe Su, Chengdu, CN;
Ching-chuan Kuo, Taipei, TW;
Tiesheng Yan, Chengdu, CN;
Youling Li, Shenzhen, CN;
Feng Lin, Chengdu, CN;
Xinhe Su, Chengdu, CN;
Ching-Chuan Kuo, Taipei, TW;
O2Micro Inc, Santa Clara, CA (US);
Abstract
A driving circuit includes a first inductor coupled in series with a light source for providing power to the light source. A controller coupled to the first inductor can control a switch coupled to the first inductor, thereby controlling a current flowing through the first inductor. A current sensor coupled to the first inductor can provide a first signal indicative of the current flowing through the first inductor, regardless of whether the switch is on or off. The switch is controlled according to the first signal. A second inductor magnetically coupled to the first inductor is also electrically coupled to the first inductor via a common node between the switch and the first inductor for providing a reference ground for the controller. The reference ground is different from the ground of the driving circuit.