Patent ID: 6049321
Filing Date: 2000-04-11
Classification: G09G

Abstract:
A liquid crystal display comprising:a matrix array of liquid crystal pixels;a plurality of signal lines formed along columns of the liquid crystal pixels;a plurality of driving transistors assigned to said liquid crystal pixels, for causing said signal lines to be electrically connected to the liquid crystal pixels of a selected row; anda signal line driver for driving said signal lines, wherein said signal line driver includes:a signal distribution controller for causing digital pixel signals serially supplied for the liquid crystal pixels of the selected row to be output in parallel,a plurality of D/A converters arranged to correspond to said signal lines, for converting digital pixel signals output in parallel from said signal distribution controller into analog pixel signals,an amplifying section for amplifying the pixel signals obtained from the D/A converters, anda switch section for outputting the pixel signals obtained from the amplifying section to the signal lines;said amplifying section includes groups of first and second amplifying circuits for amplifying the pixel signals obtained from adjacent two of said D/A converters in different polarities;said first amplifying circuit is connected to a first power source to amplify the pixel signal in a positive polarity;said second amplifying circuit is connected to a second power source to amplify the pixel signal in a negative polarity;said switch section includes a plurality of switch circuits each for periodically exchanging adjacent two of said signal lines which receive the pixel signals obtained from said first and second amplifying circuits of a corresponding group;each switch circuit includes a first switching element connected between said first amplifying circuit and one of said adjacent two signal lines, a second switching element connected between said first amplifying circuit and the other one of said adjacent two signal lines, a third switching element connected between said second amplifying circuit and the one of said adjacent two signal lines, and a fourth switching element connected between said second amplifying circuit and the other one of said adjacent two signal lines;a pair of first and fourth switching elements and a pair of said second and third switching elements are controlled to alternately turn on in predetermined cycles by a control signal supplied externally;said first and second switching elements are constituted by transistors of a first conductivity type; andsaid third and fourth switching elements are constituted by transistors of a second conductivity type.