Constant current linear driver with high power factor
US10548188B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Feb 25, 2019 |
| Grant date | Jan 28, 2020 |
| Priority date | — |
| Expiry date | Feb 25, 2039 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A controller for controlling a plurality of serially-connected LED strings includes a reference voltage generator configured to generate a plurality of reference voltages. The reference voltage generator is further configured to vary the plurality of reference voltages based on a sampled voltage signal. The sampled voltage signal can include one or both of a peak voltage of the rectified input AC voltage and a peak voltage of an LED diode forward voltage Vf. The controller further includes a plurality of linear regulators, each linear regulator coupled between a cathode of a corresponding LED string and a common current sense node, and each linear regulator is configured to regulate a current through a corresponding LED string according to a corresponding reference voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.