Patent · US Expired

Driver circuit and method for driving electroluminescent lamp to emit light at brightness set level

US7081720B2 · kind B2 · utility

8Cited by

9References

8Claims

0Family size

Assignee

Siemens Aktiengesellschaft · DE

Inventors

Alf Burau · Dortmund, DE
Heinrich Noll · Groß-Umstadt, DE
Peter Schilling · Siebnen, CH
Jürgen Wenning · Mainaschaff, DE

Key dates

Filing date	May 27, 2004
Grant date	Jul 25, 2006
Priority date	—
Expiry date	May 27, 2024

Classification

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

Abstract

A method for driving an electroluminescent lamp to emit light at a brightness set level includes providing a variable bias voltage to the electroluminescent lamp. The variable bias voltage is increased with the duration of the on-time of the electroluminescent lamp. To stabilize the electroluminescent lamp at the brightness set level against aging, a closed loop control of the brightness of the electroluminescent lamp is applied, which is subject to said duration of the on-time the electroluminescent lamp.

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