Patent · US Expired

Display driver circuits

US7535441B2 · kind B2 · utility

5Cited by
14References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 14, 2003
Grant dateMay 19, 2009
Priority date
Expiry dateOct 23, 2023

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E60/36
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Display driver circuits are described for driving organic light emitting diode displays, particularly passive matrix displays, with greater efficiency. The display drivers comprise a controllable current generator to provide a variable current drive output to an OLED display, the current generator comprising at least one bipolar transistor in series with the current drive output. The display brightness is adjustable by controlling the current generator to vary the current drive to the display. Preferably the bipolar transistor has an emitter terminal substantially directly connected to a power supply line of the driver to reduce losses in the driver. A corresponding method is also described. By employing a bipolar transistor current drive and varying display brightness by controlling the current an efficient driver-display combination is obtained.

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