Patent · US Active

Method for controlling an electrical light source by pulse width modulation

US7888890B2 · kind B2 · utility

11Cited by

4References

5Claims

0Family size

Assignee

Conti Temic microelectronic GmbH · DE

Inventors

Uli Joos · Nonnenhorn, DE
Christian Voss · Geretsried, DE
Josef Schnell · Vergennes, US
Jochen Zwick · Markdorf, DE

Key dates

Filing date	Jul 14, 2005
Grant date	Feb 15, 2011
Priority date	—
Expiry date	Nov 28, 2027

Classification

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

Abstract

A method for controlling electrical light sources, in particular, light-emitting diodes (LEDs) by pulse width modulation of a supply voltage is disclosed, whereby the supply voltage or a parameter dependent thereon, for example the current or the electrical power, is measured and the pulse width is controlled as a function thereof. According to the invention, for the light source a characteristic curve for the brightness is generated as a function of the supply voltage or the parameter dependent thereon and, from the measured supply voltage or the parameter dependent thereon, an actual brightness value is determined with the characteristic curve and is compared with a given brightness value and the pulse width controlled as a function thereof.

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