High-reliability gate driver on array using noise sharing of precharging node for thin film transistor-liquid crystal display application

Abstract

A hydrogenated amorphous silicon (a-Si:H) thin-film transistor (TFT) gate driver with negative bias stress on precharging node for noise sharing with high-reliability 10.7-in. automotive display has been proposed. The proposed circuit is composed of precharging block, pull-up and pull-down block, and noise-free block. The precharging block not only starts up the gate driver but also reduces noise with 33% duty cycle. Duplicate output signals are responsible for turning on next stage to decrease the loading of output of gate line. Moreover, negative bias voltage recovering of TFTs could be created by setting another lower voltage source to lower the threshold voltage degradation of TFTs. According to lifetime test results, the proposed gate driver of 708 stages passes the extreme temperature range test (90 degrees C and -40 degrees C) for simulation and -40 degrees C for measurement and remains stable over 800 h at 90 degrees C test. Finally, this design is successfully demonstrated in a 10.7-in. HD (1280 x RGB x 720) TFT-LCD panel.