Driver circuit for LED vehicle lamp
US7042165B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 26, 2004 |
| Grant date | May 9, 2006 |
| Priority date | — |
| Expiry date | Oct 1, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/54
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A first vehicle lamp driver circuit for a light emitting diode (LED) array, the LED array having a first string of four LEDs in series and a second string of four LEDs in series. A first LED driver drives the first LED string and a second LED driver drives the second LED string. In a STOP mode of operation, the current to both LED strings is controlled by the LED driver in series with the LED string. In a TAIL mode of operation, the current is provided to only one LED string via a series connected diode and resistor. When there is reduced input voltage, operation of the LED strings is provided by switching circuits that short-out one LED in each LED string. A second vehicle lamp driver circuit comprises a first LED string and a second LED string in series with a control switch having a feedback circuit for maintaining constant current regulation to control the sum of the current in each LED string and reduce switching noise.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.