Sampling external voltage which may exceed integrated circuit maximum voltage rating
US8461764B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 11, 2011 |
| Grant date | Jun 11, 2013 |
| Priority date | — |
| Expiry date | Jan 31, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An LED driver arrangement wherein a low voltage IC is arranged to sample the voltage at a terminal of each of the respective electronically controlled switches controlling a plurality of LED strings each receiving power from a single source, with the single source providing voltage in excess of the voltage rating of the IC. For each electronically controlled switch a controllable current source and an isolating unidirectional electronic valve is provided, the respective current source being enabled only when the respective associated electronically controlled switch is at least partially closed thereby ensuring that the respective isolating unidirectional electronic valve associated with the respective illuminating LED string conducts, and the voltage at the terminal of the respective electronically controlled switch is thus seen by the IC when the associated LED string is producing illumination, the voltage then being lower than the maximum voltage rating of the IC.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.