LIQUID CRYSTAL DRIVING VOLTAGE GENERATOR MINIMIZING CONTRAST VARIATION BY TEMPERATURE COMPENSATION AND ITS METHOD

摘要

PURPOSE: A liquid crystal driving voltage generator minimizing contrast variation by temperature compensation and its method are provided which senses external temperature and applies a temperature coefficient(k) of a reference driving voltage according to temperature variation differently, depending on external temperature variation. CONSTITUTION: A reference voltage generation part(110) generates a reference DC voltage and a reference temperature display voltage varying according to external temperature variation, and generates a reference liquid crystal driving voltage by processing a reference gray voltage corresponding to selected temperature coefficient information. The first amplifier(120) outputs a liquid crystal voltage by amplifying the reference liquid crystal driving voltage. The second amplifier(130) outputs a reference temperature voltage by amplifying the reference DC voltage. The third amplifier(140) outputs a temperature display voltage by amplifying the reference temperature display voltage. And a temperature coefficient selection part(150) generates 3 bit latch input information and selects an external input temperature coefficient corresponding to the 3 bit latch input information, and outputs the selected temperature coefficient information.