An OP-AMP Structure for Reducing Size of Driver ICs in TFT-LCDs

摘要

An OP-AMP structure was proposed that can not only drive source lines of TFT-LCD but also sum two signals in voltage domain. In realizing the two-voltage summing function, the OP-AMP adopts neither multiple resistor-string structures nor switched-capacitor circuits as most of previous works did. So, the accuracy of a summed voltage is free from many various problems, which are generated in those circuits. HSPICE simulation verified that mis-summing voltages reach just tens of mico-volts and high accuracy is attained. This circuit is expected to enable the conventional DAC-dividing schemes, which reduce size ofDAC decoder, to be adopted in driver IC without any deteriorations of accuracy and any corruptions of γ -correcting functions.