Innovative Voltage Driving Pixel Circuit Using Organic Thin-Film Transistor for AMOLEDs

Abstract

In this work, we propose a novel active-matrix organic light-emitting diode displays (AMOLED) pixel circuit based on organic thin-film transistor (OTFT) architecture, which consisted of four switches, one driving transistor, and a capacitor. The pentacene-based OTFT device possesses a field-effect mobility of 0.1 cm(2)/V . s, a threshold voltage of -1.5 V, subthreshold slope of 1.8 V/decade and an on/off current ratio 10(6). The resultant voltage-driving pixel circuit, named "Complementary Voltage-Induced Coupling Driving" (CVICD), is different from the current-driving scheme and can appropriately operate at low gray level for the low-mobility OTFT circuitry. The current non-uniformity less than 2.9 % is achieved for data voltage ranging from 1 to 17 V by SPICE simulation work. In addition, the new external driving method can effectively reduce the complexity of OLED pixel circuitry.