Patent ID: 6184855
Filing Date: 2001-02-06
Classification: G09G

Abstract:
An LCD panel driver, comprising:a first plurality of sample hold and buffer amplification units for positive inputs each including a sample hold circuit for sampling and holding an input video signal having a positive polarity in response to a first control signal and having a first buffer amplifier activated during said holding for charging a data line in an LCD panel;a second plurality of sample hold and buffer amplification units for negative input each including a sample hold circuit for sampling and holding an input video signal having a negative polarity in response to a second control signal and having a buffer amplifies activated during said holding for discharging a data line in the LCD panel;an output selector for selecting in response to a third control signal one or another of said buffer amplifies in a group including one of said first plurality of sample hold and buffer amplification units for positive input and one of said second plurality of sample hold and buffer amplification units for negative inputs, said outputs selector having means for making said data line a common voltage selected to reduce power consumption by the buffer amplifiers while neither buffer amplifier in the group is selected;a bidirectional shift register for generating sampling pulses; anda controller for generating said first and second control signals which control the timing of sampling and holding in said sample hold circuits and said third control signal from a mode specification signal specifying whether one-sided drive or two-sided drive, and HV inversion or H inversion are performed, a fourth control signal created in response to a Horizontal sync. signal and Vertical sync. signal to control the polarity of output voltage to said LCD panel and said sampling pulses.