LED drive apparatus, systems and methods
US9554435B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 2013 |
| Grant date | Jan 24, 2017 |
| Priority date | — |
| Expiry date | May 21, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B47/11
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Light flux levels sensed from a color LED array control both current availability to the array and disable/re-enable a current bypass switch to shunt stored-energy current to or away from a selected LED. In continuous mode, a single flux pulse is created for the duration of a pre-established period. Feedback from the flux sensor pulses current to an energy storage device to maintain the light flux at a predetermined set-point. A particular dimming level is achieved by establishing both the pulse period and the flux magnitude. In discontinuous mode, one or more short flux pulses are created. Both the turn-on and the turn-off time of each flux pulse is controlled by alternately removing and then re-establishing a current shunt from the energy storage device to ground. Flux pulse magnitude is controlled by recognizing when the flux pulse has reached a predetermined set-point and re-establishing the current shunt to abruptly turn off current to the selected LED.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.