Patent · US Expired

Driving circuits for a passive matrix LCD which uses orthogonal functions to select different groups of scanning electrodes

US5818409A · kind A · utility

21Cited by
8References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 21, 1995
Grant dateOct 6, 1998
Priority date
Expiry dateDec 21, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2320/0204
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A data electrode driving circuit, a scanning electrode driving circuit, a liquid crystal display unit and a driving method thereof for attaining simultaneous scanning and driving of a plurality of rows in a passive matrix type liquid crystal display unit. A scanning electrode driving circuit includes a scanning function generating circuit for generating scanning functions for m rows. A scanning voltage is selected by the scanning function and a driving voltage is supplied to the scanning electrode. On the other hand, a data electrode driving circuit includes shift registers for m rows. The shift registers produce display data for m rows taken therein at the same time. The display data for m rows and the scanning function produced by the scanning electrode driving circuits are subjected to comparison operation. One level of m+1 level voltages is selected in accordance with the operation result and is supplied to the data electrode. The liquid crystal panel performs display in accordance with the voltage for the scanning electrode and the voltage for the data electrode.

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