Patent ID: 7760179

Claim:
A data driver for driving a liquid crystal display panel including a plurality of gate lines, a plurality of first data lines and a plurality of second data lines crossing the gate lines, and a plurality of pixels defined by crossings of a plurality of gate lines with a plurality of first data lines and a plurality of second data lines, wherein each of the pixels includes a first thin film transistor connected to a gate line and a first data line, a second thin film transistor connected to the gate line and the second data line, and a liquid crystal cell connected between the first and second thin film transistors, the data driver comprising: a division unit that divides an input data signal into first and second data signals; a shift register that sequentially outputs a latch enable signal; a latch unit that latches the divided first and second data signals in response to the latch enable signal; and a digital to analog converter that outputs first and second data voltages corresponding to the first and second data signals using a plurality of positive polarity gamma voltages and a plurality of negative polarity gamma voltages, wherein a voltage level of each first data voltage is symmetric to that of a respective second data voltage with respect to a reference voltage, wherein the digital to analog converter includes: a first multiplexer that outputs the first data voltage corresponding to the first data signal; a second multiplexer that outputs the second data voltage corresponding to the second data signal; and a switch that alternately supplies the plurality of positive polarity gamma voltages and the plurality of negative polarity gamma voltages to the first and second multiplexers at every predetermined period.