LIQUID CRYSTAL DISPLAY TO EASILY ADJUST A CONTRAST RATIO WITHOUT USING A MEMORY DEVICE

摘要

PURPOSE: A liquid crystal display is provided to easily adjust a contrast ratio without using a memory device, thereby reducing the manufacturing cost and controlling brightness of a screen according to a user. CONSTITUTION: An analog voltage signal generator(400) preliminarily stores a synchronous signal and a digital data signal inputted in response to a write enable signal, and converts the digital data signal in response to an output enable signal for generating a plurality of analog voltage signal pairs. A plurality of reference voltage generators(420) output a plurality of reference voltages respectively by distributing power voltages boosted according to the signals generated from the analog voltage signal generator. A source drive IC(Integrated Circuit)(440) receives the plurality of reference voltages. If a command for changing reference voltage values is transmitted to a digital-to-analog converter(404) of the analog voltage signal generator, the digital-to-analog converter changes the reference voltage values and outputs the changed reference voltage values to the plurality of reference voltage generators so that a range of a contrast ratio is converted by the changed reference voltage values.