Convolution-Based Vth Shift Prediction and the New 9T2C Pixel Circuit in LTPS TFT AMOLED

In this paper, we developed a new convolution-based methodology to estimate the dynamic time-evolutionary degradation of pixel circuits in display applications. This method not only facilitates more precise circuit-level estimation but also considers the dynamic voltage stress encountered in pixel circuit operations. For the first time, we have enabled realtime observation of the threshold voltage changes over time in key driving TFTs under different bias conditions in transient simulations of pixel circuits. Additionally, we introduce an optimized 9T2C pixel compensation circuit. Compared to the classic 7T1C pixel circuit, our proposed 9T2C circuit compensates for the OLED current degradation caused by DTFT (driving TFT) degradation during the emission phase, reducing the current disparity to 0.39 μA at 1 second. This is an approximately 50% improvement over the 0.73 μA observed in the 7T 1C configuration.