51.1: A 2.5‐inch OLED Display with a Three‐TFT Pixel Circuit for Clamped Inverter Driving

A new pixel circuit for “clamped inverter driving” was developed. Since a PMOS inverter is applied instead of the conventional CMOS for the pixel circuit, the circuit is simplified and is composed of only three TFTs. A simulation of gray-scale characteristics verified that this pixel circuit can compensate variation in Vth and carrier mobility. A 2.5-inch OLED display based on the new pixel circuit was fabricated by LTPS processing and achieves 6-bit gray-scale and good uniformity.