Drive circuit for light emitting diode
US7479738B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 23, 2007 |
| Grant date | Jan 20, 2009 |
| Priority date | — |
| Expiry date | Apr 27, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/52
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A drive circuit for light emitting diode (LED) is provided, which is used to drive a plurality of LEDs to emit light. The LEDs are connected in series into a plurality of LED strings. The drive circuit includes a power converter, a detection circuit, and a report circuit. The power converter provides a driving voltage to the LED strings, and the detection circuit detects a string voltage of each LED string, and compares the string voltage with a default reference voltage, so as to determine whether the string voltage is different from the reference voltage (which indicates that the LED string is operated under a non-default state), and sends a detection signal to the report circuit. The report circuit receives the detection signal and outputs the control signal to the power converter, such that the power converter adjusts the driving voltage according to the control signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.