An a-IGZO TFT pixel circuit for AMOLED with simultaneous VT compensation

In this paper, a four a-IGZO TFTs based pixel circuit with simultaneous V_T compensation function for AMOLED is proposed. The proposed circuit can not only simplify the peripheral circuits of the panel, but also compensate for both positive and negative V_T shift with a charging V_T-generation method. Simulation results show that the current changes only by 18.9% and 3.9% when ΔV_T is -3 V and 2 V, respectively. Furthermore, by applying the grouping driving scheme, the OLED lighting time can be largely increased which manifests superiority when applied to high resolution or high frame rate displays.