Patent · US Expired

Active matrix drive circuit

US7432891B2 · kind B2 · utility

7Cited by
3References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 20, 2003
Grant dateOct 7, 2008
Priority date
Expiry dateJul 5, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2320/043
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A driving circuit for an image point of an image screen which has an organic light-emitting diode includes a capacitor, a feedback coupling, a first thin film transistor as a current-driving transistor for the diode, a second transistor which is connected by a current-conducting electrode with a gate of the first transistor and by a second current-conducting electrode with a data conductor and by its gate electrode with a scanning signal conductor, a third thin film transistor which during driving its gate through a driving conductor taps a diode driving current and an output of the first transistor and supplies a current measuring- and voltage regulating circuit, the current measuring- and voltage regulating circuit providing to the data conductor a voltage signal which is dependent on a current measuring result and a voltage comparison, so that the diode during driving of the gate of the third transistor due to its non-linear switching characteristic acts as a switch for a current deviation in the current measuring- and voltage regulating circuit.

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