LED drive apparatus, systems and methods
US9907135B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 2017 |
| Grant date | Feb 27, 2018 |
| Priority date | — |
| Expiry date | Jan 20, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B47/11
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
For controlling a level of luminance produced by a color light-emitting diode (LED) array, a method includes: for a predetermined flux bit-slice period, activating a color enable signal to select a primary color LED and to select a predetermined light flux magnitude set-point; selectively charging an energy storage device and discharging the energy storage device through the selected primary color LED to generate a light flux output during the flux bit-slice period; adjusting a rate of selectively charging the energy storage device to maintain a magnitude of the light flux output at the predetermined light flux magnitude set-point during the flux bit-slice period; and adjusting the predetermined light flux magnitude set-point over the life of the selected LED as the selected LED ages as a function of an anode-to-cathode voltage drop across the selected LED for a given magnitude of current flowing through the selected LED.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.