Constant-current driving circuit
US7961158B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 2007 |
| Grant date | Jun 14, 2011 |
| Priority date | — |
| Expiry date | Apr 12, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A constant-current driving circuit includes a first current source, a reference voltage generating circuit and an output signal generating circuit. A terminal of the first current source is coupled to a terminal of a first LED string, wherein the terminal of the first current source has a first voltage. The reference voltage generating circuit is used for generating a reference voltage and comparing the first voltage with a first predetermined voltage to generate a first comparing signal to thereby adjust the reference voltage. The output signal generating circuit is used for outputting an output signal to another terminal of the first LED string and receiving the input signal, wherein the output signal generating circuit decides whether or not to output the input signal serving as the output signal according to the comparison result of the reference voltage with the second voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.