Driving Electronics Of The EL And AMOLED

EL (Electroluminescent) and AMOLED (Organic Light Emitting Display) have already being engaged into research all over the world because of their solid state construction which can make them working in the severe environment. It will help them occupy part of the display market sooner or later.In this paper, the driving methods of EL was presented and schematics of the circuit using the symmetric drive methods was showed firstly, then a driving circuit system diagram for AMOLED was introduced. Using LCD driver IC, the logic control circuit in FPGA designed by VHDL is proposed. We utilize the COFs to address the correct voltage values to the TFTs and then we use Vdd to supply the current to drive the OLED pixel. The chips we use are SOLOMON SSD1205 for row drivers and SSD1213 for column drivers. Now, even though column drivers have 6 outputs per pixel (3 positive RGB and 3negative RGB for LCD use), we only connect to one of those outputs to our OLED pixel as Vgamma input. Row drives only turn on and off T1 gates to pass data voltage to the T2 transistor. If panels get bigger we can connect those row drivers in series since they only have 240 outputs. In order to avoid losses during the digital video signal transmission, we bring digital video interface (DVI) into this driving system.After getting the expected simulation result in Modelsim, the code was downloaded to the Xilinx Spartan XC3S2000, and obtained a good quality showing on the 5-inch (320×240) AMOLED screen produced by SVA Electron Inc.