Patent · US Expired

Constant current driver with auto-clamped pre-charge function

US6323631A · kind A · utility

226Cited by
3References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 18, 2001
Grant dateNov 27, 2001
Priority date
Expiry dateJan 18, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2320/0252
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A constant current driver with auto-clamped pre-charge function includes a reference bias generator and a plurality of constant current driver cells, each being connected to the reference bias generator to form a respective current mirror. Each constant current driver cell has a switch transistor, a current output transistor and a pre-charge transistor. When a constant current is outputted from the current output transistor for driving an organic light emitting diode, the pre-charge transistor is turned on to provide a drain to source current as an additional large current for rapidly pre-charging the organic light emitting diode until the gate to source voltage of the pre-charge transistor is smaller than the threshold voltage.

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