Control circuit and method for backlight sources, and image display apparatus and lighting apparatus using the same
US8193734B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 2009 |
| Grant date | Jun 5, 2012 |
| Priority date | — |
| Expiry date | Jan 20, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2360/145
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An light emitting diode (LED) control, a plurality of duty cycle signals corresponding to a plurality of LEDs are stored in a dual-port memory by memory mapping. By sampling, the stored duty cycle signals are outputted to generate a plurality of parallel single-bit data each having one single bit. After the single-bit data are converted by a data transmission module, each bit of the single-bit data is serially outputted to a drive module to drive the LEDs. Thus, the ON duty cycles of the LEDs are modulated by pulse width modulation (PWM), light emitted from the LEDs are mixed in time-domain, and the brightness of the LEDs can be controlled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.