Patent · US Active

Backlight driving system utilizing one PWM controller to control two backlight units separately

US8247996B2 · kind B2 · utility

0Cited by
4References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 26, 2010
Grant dateAug 21, 2012
Priority date
Expiry dateApr 8, 2031

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B20/00
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A backlight driving system comprises a first inverter circuit, a second inverter circuit, a pulse width modulation (PWM) controller, a frequency regulator and a switch circuit. The pulse width modulation (PWM) controller generates an illumination signal to control the first and second inverter circuits to illuminate first and second backlight units in response to a first enable signal, and generates a maintaining signal to control the first and second inverter circuits to maintain stable lighting of the first and second backlight units in response to a first feedback signal. The frequency regulator controls the PWM controller to generate the illumination signal and the maintaining signal in response to a second enable signal and a second feedback signal, respectively. The switch circuit connects the PWM controller to the second inverter circuit in response to the second enable signal.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.