Affiliation:
1. Large Display Business Unit, LG Display Paju Korea
Abstract
In this paper, we present the small area and high reliable gate driver in panels using a‐IGZO TFTs for large OLED displays. The proposed gate driver circuit has a small area structure with multiple output buffers connected to one shift register circuit. To lower the voltage stress of the pull‐down TFTs, which have the highest voltage stress among the TFTs of the gate driver, the initial voltage of those TFTs is set to low and increases according to the threshold voltage shift of TFTs during operation. It could be implemented by sensing the degradation of the TFTs using the programmable DC driving method. With these technologies, we were able to reduce the gate driver design area by 40% and improve the reliability by 30% despite reducing the circuit area. We successfully developed OLED TVs from 42 inches to 97 inches using the proposed gate driver.