A new threshold-voltage compensation technique of IGZO and LTPS for AMOLED display pixel circuit

This work presents a voltage programmable pixel circuit with a new threshold-voltage compensation technique for AMOLED displays using Indium Gallium Zinc oxide thin-film transistors (IGZO-TFT) or Low-Temperature Polycrystalline Silicon (LTPS-TFT). One of the advantages of the proposed pixel design is the simplicity of the circuit due to the fact that it requires only four TFTs and one capacitor. The main advantage of the proposed pixel design is that the current of the OLED is almost independent of the threshold voltage of the driving TFT and well controlled. Also, the threshold voltage compensation technique is implementing with a static circuit, resulting to fast response time, similar to the conventional 2T1C response time which is the fastest circuit.