Bi-directional gate driver on array with controllable TDDM block for in-cell touch display

This article proposes a novel gate driver circuit using amorphous silicon (a-Si) with the dual function of a noise-eliminating block for in-cell touch liquid–crystal display. Compared to earlier circuit designs, the proposed circuit eliminates the requirement for an additional block to transfer the long-term DC stress of the driving TFT during the touch operation. Moreover, the circuit in this article could freely choose when to execute touch operations, thereby mitigating node degradation within the circuit and enhancing the reliability of the circuit. The proposed circuit also has the function of bidirectional scanning to achieve the effect of image inversion and enhance the flexibility of the panel. The simulation results show the circuit exhibits no distortion in its output after a 1000 µs touch period. The result indicates the effective prevention of leakage current of the proposed circuit during the touch operation. Measurement results indicate that the circuit could successfully operate at 85 °C for intervals of 2000 µs. Finally, the proposed circuit could be realized for 5.3-inch Full HD (720*RGB*1280) in-cell touch panels and showed the potential to use in large interactive touch panel application.