The present invention relates to a LCOS display driving system. The driving sequential control block generates a control code representing a loading sequence of the R, G, and B data for pixels in one of scan lines. The multiplexer multiplexes the R, G, and B data from latches according the control code. The shared level shifter shifts the level of the R, G, and B data from the multiplexer. The digital analog converts converting the R, G, and B data to a corresponding analog R, G, and B data voltage. The shared unity-gain buffer stores the analog R, G, and B data voltage from the shared digital analog converter. The demultiplexer demultiplexes the analog R, G, and B data voltage according the control code.