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. 23, 2014
Filed:
May. 30, 2012
Chih-wei Chu, New Taipei, TW;
Yu-nan Yen, Zhudong Township,Hsinchu County, TW;
Chih-Wei Chu, New Taipei, TW;
Yu-Nan Yen, Zhudong Township,Hsinchu County, TW;
Raydium Semiconductor Corporation, Hsinchu County, TW;
Abstract
A light-emitting diode (LED) driver is provided. The LED driver, providing a drive voltage for driving an LED circuit according to an input voltage, includes a current regulator, a dimming signal generator, and a boost converter. In response to a pulse width modulation (PWM) dimming signal, the current regulator enables the LED circuit in a first PWM period and disables the LED circuit outside the first PWM period. The dimming generator generates a prolonged PWM dimming signal according to the PWM dimming signal. The prolonged PWM dimming signal has a prolonged period, a length of which is associated with a level of an input voltage. In response to the prolonged PWM dimming signal, the boost converter is enabled in a second PWM period and maintains a level of the drive voltage according to the input voltage.