Patent · US Active

Sigma delta current source and LED driver

US8278840B2 · kind B2 · utility

47Cited by
9References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 8, 2010
Grant dateOct 2, 2012
Priority date
Expiry dateNov 30, 2030

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B20/30
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A circuit arrangement includes a first light emitting diode and a second light emitting diode emitting light of different colors arranged adjacent to each other for additive color mixing. A first and second controllable current sources are connected to the first and second light emitting diode, respectively, such that the load currents of the light emitting diodes depend on respective control signals received by the current sources. First and second sigma-delta modulators are connected to the first and second light emitting diodes, respectively, and provide bit-streams as control signals to the current sources. The mean value of each bit-stream corresponds to the value of an input signal of the respective sigma-delta modulator.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.