Patent ID: 7030840
Filing Date: 2006-04-18
Classification: G09G

Abstract:
1. A display device comprising: a plurality of pixels each of which has one of different luminosity characteristics; a plurality of signal line blocks each including a preset number of signal lines connected to said pixels having a common one of the luminosity characteristics; and a signal line driving circuit which drives said signal lines according to a video signal, said signal line driving circuit including a selection circuit which sequentially selects the signal line blocks in an effective picture period of the video signal and a driving unit which drives the preset number of signal lines included in the signal line block selected by the selection circuit, wherein said signal line driving circuit further includes a reference gradation voltage generating circuit which divides a reference power supply voltage at a voltage dividing ratio changed for the signal line block selected by said selection circuit to generate a group of reference gradation voltages, said driving unit includes a data bus which receives the video signal in a digital form, a data register which sequentially latches the video signal on the data bus during an effective picture period of the video signal, and a digital-to-analog converting circuit which converts the video signal output in parallel from said data register into analog voltages with reference to the group of reference gradation voltages generated by said reference gradation voltage generating circuit, said selection circuit includes a preset number of switch sections which electrically connect a preset number of signal lines included in each signal line block to a preset number of output terminals provided in said driving unit, and said reference gradation voltage generating circuit includes a ladder resistor, and a voltage dividing ratio controller connected in series with said ladder resistor between a pair of power terminals which receive the reference power voltage, said voltage dividing ratio controller having a plurality of variable resistors each corresponding to one of the different luminosity characteristics, a plurality of switching elements respectively connected in series with said variable resistors and controlled to synchronize with a changeover between said switch sections.