Unbalanced plural string LED driver with common return resistor
US7642725B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 17, 2006 |
| Grant date | Jan 5, 2010 |
| Priority date | — |
| Expiry date | Jun 24, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present disclosure describes systems and methods for driving light emitting diodes (LEDs). At least some embodiments include an LED driver system that includes a power supply, a plurality of current sources (each current source coupled between a common return resistor and one of a plurality of branches of series coupled LEDs, and each branch coupled between a corresponding current source and the power supply), and control logic coupled to the current sources (the control logic capable of controlling the current flow through each current source). Each of the current sources allows current to flow during one of a plurality of substantially non-overlapping time periods within a repeating time interval, each current source allowing current to flow during a different time period. The magnitude of the current flowing through each current source is substantially the same and is regulated based upon a feedback voltage across the common return resistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.