Digital driver apparatus, method and system for solid state lighting
US7880400B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 21, 2007 |
| Grant date | Feb 1, 2011 |
| Priority date | — |
| Expiry date | Jun 13, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/375
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An apparatus, method and system are provided for controlling the solid state lighting, such as LEDs. An exemplary apparatus comprises: a switch for switching electrical current through the LEDs, a current sensor; a first comparator adapted to determine when a switch electrical current has reached a first predetermined threshold; a second comparator adapted to determine when the switch electrical current has reached a predetermined average current level; and a controller. The controller is adapted to turn the switch into an on state and an off state, to determine a first on time period as a duration between either a detection of a second predetermined current threshold or the turning the switch into the on state, and the detection of the predetermined average current level; to determine a second on time period as a duration between the detection of the predetermined average current level and the detection of the first predetermined current threshold; and to determine an on time period of the switch as substantially proportional to a sum of the first on time period and the second on time period. Additional exemplary embodiments utilize a difference between the first and second on tim…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.