High Vth Compensation Range AMOLED Pixel Circuit Based on A Dual Gate a-IGZO TFT and A Specially Amplified Capacitor

This article presents a new voltage-programmed pixel circuit based on a dual gate a-IGZO thin film transistor (TFT) and a specially amplified capacitor (C) to effectively compensate threshold voltage (Vth) variations of a dual gate driving TFT, which can maintain the pixel brightness of active matrix organic light-emitting diodes (AMOLED) displays. The proposed new circuit contains six TFTs and three capacitors. The focus of this paper is using a dual gate TFT and introducing an amplified capacitor to regulate the gate node potential of driving TFT, which can greatly broaden the Vth compensation range of the driving TFT from -1.0 V~1.0 V to -1.8 V~2.4 V by means of simulation.