LED light source
US9113524B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 19, 2012 |
| Grant date | Aug 18, 2015 |
| Priority date | — |
| Expiry date | May 12, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/48
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A series arrangement of LED loads (LP1-LP4) is coupled between output terminals of a rectifier having its input terminals coupled to a mains supply supplying a low frequency AC voltage. Control means render the LED loads conductive one by one, when the amplitude of the supply voltage increases, and non-conductive one by one when the amplitude of the supply voltage decreases. The first LED load (LP1, LP2) has a forward voltage that is substantially higher than that of the other LED loads. As a consequence, the LED utilization is comparatively high, thus allowing the LED loads used in the series arrangement to be comparatively cheap.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.