Driving apparatus of light emitting diode and driving method thereof
US8154223B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 1, 2009 |
| Grant date | Apr 10, 2012 |
| Priority date | — |
| Expiry date | Oct 6, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/37
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A driving apparatus of a light emitting diode (LED) and a driving method thereof are provided. In the driving method, when the driving apparatus performs dimming and a duty cycle of a dimming signal is smaller than a predetermination value, outputting time of driving currents are equally allotted in a period, and a magnitude of each driving current is regulated correspondingly. When the driving apparatus performs dimming and the duty cycle of the dimming signal is equal to or greater than the predetermination value, the driving currents are simultaneously output in the period, and the magnitude of each driving current is regulated according to the dimming signal. Therefore, an audio noise and an electromagnetic interference caused by excessive variation of a sum of the driving currents are suppressed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.