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:
Feb. 05, 2013
Filed:
Jan. 30, 2009
Tung-tsai Liao, Hsin Chu, TW;
LI Sheng Lo, Hsin Chu County, TW;
Tung-Tsai Liao, Hsin Chu, TW;
Li Sheng Lo, Hsin Chu County, TW;
Generalplus Technology Inc., Hsinchu, TW;
Abstract
The invention relates to an electronic candle and an electronic night lamp. The electronic candle includes a light-emitting diode (LED), a capacitor and a control circuit. The capacitor has a first terminal coupled to a first terminal of the LED, and a second terminal coupled to a common voltage. The control circuit has a first control terminal coupled to the first terminal of the LED, and a second control terminal coupled to a second terminal of the LED. In a detecting period, the control circuit provides a preset voltage across the first and second terminals of the LED so that the LED is reversely biased for a preset time. Then, the first control terminal of the control circuit is set to high impedance. Next, the control circuit detects a variation of a voltage of the first terminal of the capacitor with respect to time to determine whether to light up the LED.