Low voltage light source driving circuit
US8143794B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 2009 |
| Grant date | Mar 27, 2012 |
| Priority date | — |
| Expiry date | Jun 20, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A low voltage LED (Light Emitting Diode) driving circuit operates under low supply voltage to provide stable and reliable control of LEDs. The LED driving circuit includes a switching transistor to turn on or off an output current in the LED. The LED driving circuit also includes a control transistor for controlling the level of the output current. The two transistors are coupled via a node that is maintained at a low voltage to increase the voltage across the switching transistor. The increased voltage across the switching transistor allows faster switching and more stable control over different levels of output voltage. The LED driver also includes circuit components for matching the turn-on times and turn-off times for different levels of the output current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.