Multiple stage sequential current regulator
US8686651B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 15, 2011 |
| Grant date | Apr 1, 2014 |
| Priority date | — |
| Expiry date | Apr 3, 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 circuit is disclosed. The top of a string of series connected LED segments is connected to the output of a rectifier, which in turn is connected to an AC source. The string is tapped at various locations, including the bottom of the string. Each segment can consists of any number of serial or parallel connected LEDs. Current control elements or regulators sink current at each tap and are sequentially turned on and off one at a time, tracking the rectified sine wave voltage. Voltage across each regulator and current when conducting is individually controllable. The regulators may control current in a multitude of ways, including a constant current, or a current dependent on voltage across the regulators including a resistor, or a combination. The driver is self-commutating, with the sequencing of the current control elements an inherent feature closely integrated with the current control elements and providing optimal performance over variable operating conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.