Data driving apparatus and method for liquid crystal display device

A data driving apparatus for a liquid crystal display (LCD) device comprising:

• a timing controller configured to output control signals for controlling a driving of a gate driving unit and a data driving unit to display images on a liquid crystal panel;
• the gate driving unit configured to output a gate on signal to each of a plurality of gate lines of the liquid crystal panel;
• the data driving unit including a D/A converter configured to drive each of a plurality of data lines on the liquid crystal panel with a longitudinal two-dot inversion polarity system;
• and
• wherein the D/A converter comprises:
• a P-decoder configured to convert digital data into a negative grayscale voltage which is one of 64 analog grayscales and output the grayscale voltage;
• a N-decoder configured to convert digital data into a positive grayscale voltage which is one of 64 analog grayscales and output the grayscale voltage;
• an overdriving unit configured to output an overdriven negative grayscale voltage to a pair of negative pixels consecutive with each other and an overdriven positive grayscale voltage to a pair of positive pixels consecutive with each other in the form of overdriven negative and positive pixel signals, the pair of negative pixels is consecutive with the pair of positive pixels;
• and
• a multiplexer directly electrically connected to the P-decoder, the N-decoder, and a single line of the overdriving unit, configured to output the overdriven negative or positive pixel signals to only a first pixel or output the overdriven negative and positive pixel signals to all pixels in the pairs of the negative and the positive pixels, respectively, through conversion into a first or a second pixel signals which are consecutive with each other in a longitudinal direction, while the multiplexer is selecting the negative grayscale voltage outputted from the P-decoder or the positive grayscale voltage outputted from the N-decoder and the overdriven negative grayscale voltage and the overdriven positive grayscale voltage, and outputting the first or the second pixel signals according to the longitudinal two-dot inversion system,
• wherein the multiplexer selects the overdriven negative or positive grayscale voltage outputted from the single line of the overdriving unit at an initial portion of the first pixel signal and the multiplexer selects the negative or positive grayscale voltage outputted from the P-decoder or N-decoder for a remaining portion of the first pixel signal and for the second pixel signal or the multiplexer consecutively selects the overdriven negative or positive grayscale voltage outputted from the single line of the overdriving unit at an initial portion of the first and the second pixel signals and the multiplexer selects the negative or positive grayscale voltage outputted from the P-decoder or N-decoder at a remaining portion of the first and the second pixel signals.