Liquid crystal display and driving method thereof

A method of driving a liquid crystal display including a liquid crystal display panel having a plurality of data lines, a plurality of gate lines, a plurality of liquid crystal cells, a data driving circuit to convert digital video data into a data voltage to be supplied to the data lines and to convert a polarity of the data voltage, and a gate driving circuit to sequentially supply a scan pulse to the gate lines, the method comprising the steps of:

• determining gray levels of digital video data and a time at which the polarity of the data voltage to be supplied to the data lines is inverted;
• generating a dynamic charge share control signal to indicate a time at which the gray level of the data voltage is changed from a white gray level to a black gray level and a time at which the polarity of the data voltage is inverted;
• detecting a weakness pattern in which data of the white gray level and the black gray level are regularly arranged in the digital video data and generating a dot inversion control signal to widen a horizontal polarity inversion time of data voltages to be supplied to the data lines when the weakness pattern is input;
• converting the digital video data into the data voltage, changing the polarity of the data voltage, and supplying any one of a common voltage and a charge share voltage between a positive data voltage and a negative data voltage to the data lines in response to the dynamic charge share control signal;
• and
• widening the horizontal polarity inversion time of the data voltages in response to the dot inversion control signal,
• wherein the liquid crystal display panel includes first and second liquid crystal cell groups whose polarity is inverted every 2 frame periods and a polarity inversion time of the first liquid crystal cell group is controlled to overlap with a polarity inversion time of the second liquid crystal cell group, and
• wherein charge sharing is performed using any one of the common voltage and the charge share voltage only when the gray level of the input digital video data is changed from the white gray level to the black gray level and the polarity of the data voltages supplied to the liquid crystal display panel is inverted.