Device and method for driving LED
US7564198B2 · kind B2 · utility
78Cited by
1References
13Claims
0Family size
Assignee
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Key dates
| Filing date | Aug 29, 2007 |
| Grant date | Jul 21, 2009 |
| Priority date | — |
| Expiry date | Jan 30, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An LED lighting device of AC power-driven type having a comparatively simple constitution and a high power efficiency. The device compares a signal voltage (rectified voltage) obtained by rectifying an AC source with a predetermined reference voltage and controls ON/OFF of a driving current to each LED of an LED array in response to a comparison result. In this constitution, a large voltage of AC source enables lighting of more number of LEDs, while a small voltage thereof enables lighting of less number of LEDs, thus enhancing power efficiency of the LED lighting device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.