New Voltage Programming LTPS-TFT Pixel Scaling Down VTH Variation for AMOLED Display

A new voltage-scaled compensation pixel which employs 3 p-type poly-Si TFTs and 2 capacitors without additional control line has been proposed and verified. The proposed pixel does not employ the $V_{TH}$ memorizing and cancellation, but scales down the inevitable $V_{TH}$ variation of poly-Si TFT. Also the troublesome narrow input range of $V_{DATA}$ is increased and the $V_{DD}$ supply voltage drop is suppressed. In our experimental results, the OLED current error is successfully compensated by easily controlling the proposed voltage scaling effects.