Pulsed current averaging controller with amplitude modulation and time division multiplexing for arrays of independent pluralities of light emitting diodes
US7888881B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 2006 |
| Grant date | Feb 15, 2011 |
| Priority date | — |
| Expiry date | Sep 15, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Exemplary embodiments provide a system, method and apparatus for regulating current in loads, such as in an array of independent pluralities of light emitting diodes (“LEDs”). An exemplary system comprises a multiplexer adapted to switch current to each independent string of LEDs; a first controller to maintain a substantially constant average current level to the plurality of LEDs; and a second controller to modulate a current amplitude and duration of time division multiplexing for each independent string of LEDs. Another aspect of the system provides for modulating the on time for switching current to maintain a substantially constant average current level and to respond and converge quickly to changing current reference levels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.