초록 ▼

A liquid crystal display device significantly reduces power consumption and causes no signal delay when a liquid crystal panel performs an inversion-type drive. The liquid crystal display device comprises a digital controller, a level shift circuit, a digital-to-analog (D/A) converter, a liquid crys

A liquid crystal display device significantly reduces power consumption and causes no signal delay when a liquid crystal panel performs an inversion-type drive. The liquid crystal display device comprises a digital controller, a level shift circuit, a digital-to-analog (D/A) converter, a liquid crystal panel, and a plurality of capacitors. In the D/A converter, a charging control circuit is provided corresponding to each capacitor. The charging control circuit comprises a switch, a diode and an inverter, the switch and the diode being coupled in parallel. The switch is turned on and off in response to a switching signal from the digital controller. The switch is changed to a turning- on state during a blanking period after one horizontal displaying. Upon turning-on of the switch, the capacitors are charged. Digital pixel data outputted from the digital controller undergoes a level changing depending on a voltage across the electrodes of the capacitors, according to a charge conservation.

대표청구항 ▼

[ What is claimed is:] [14.] A liquid crystal display device, comprising:a digital control circuit which receives a first voltage and a second voltage higher than the first voltage as reference voltages and outputs first and second digital pixel data;a plurality of capacitors, one terminal of each c

[ What is claimed is:] [14.] A liquid crystal display device, comprising:a digital control circuit which receives a first voltage and a second voltage higher than the first voltage as reference voltages and outputs first and second digital pixel data;a plurality of capacitors, one terminal of each capacitor being coupled to receive said first digital pixel data;a charging control circuit, each input terminal thereof being coupled to another terminal of corresponding one of said capacitors;a first digital-to-analog (D/A) converter coupled to each output terminal of said charging control circuit, said first D/A converter receiving a fourth voltage and a fifth voltage higher than said fourth voltage as reference voltages and outputting a first analog voltage signal;a second D/A converter which receives a sixth voltage and a seventh voltage higher than said sixth voltage as reference voltages, and performing an analog conversion of said second digital pixel data, and outputs a second analog voltage signal;a switch for switching between said first and second analog voltages for either every one pixel or every one horizontal line and selectively outputting either said first analog voltage signal or said second analog voltage signal; anda display panel having a plurality of switching elements and a plurality of pixels, the display panel applying either said first analog voltage signal or said second analog voltage signal to said plurality of switching elements, each switching element being arranged in correspondence with each of said plurality of pixels,wherein after data is outputted from said charging control circuit, each said another terminal of said capacitors is charged to a third voltage, charging is stopped in order to set each said another terminal of said capacitors to a floating state, and said first digital pixel data is outputted from said digital control circuit.