LED dimming apparatus
US8339053B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 2008 |
| Grant date | Dec 25, 2012 |
| Priority date | — |
| Expiry date | Jun 8, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An LED dimming includes: current adjusting means (constant current circuit) for variably controlling a magnitude of a current flowing through an LED load; switching means (transistor) for intermittently controlling the current flowing through the LED load; and dimming controlling means (microcomputer) for controlling the current adjusting means and the switching means upon receiving a dimming signal outputted from a dimmer. In a case where the dimming signal outputted from the dimmer is on a higher brightness side than a predetermined level, the dimming controlling means flows a continuous current though the LED load, and dims the LED load based on a magnitude of the flowing current, and in a case where the dimming signal outputted from the dimmer is on a lower brightness side than the predetermined level, the dimming controlling means flows a pulse current through the LED load, and changes a mean value of waveforms of the pulse current, thereby dims the LED load. In this LED dimming apparatus, noise is less likely to occur even in a case where such an LED current is large, and brightness is less likely to vary even in a case where a dimming degree is increased.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.