Research And Development Of Driving Module For A-Si TFT OLEDs

Organic Light Emitting Diode(OLED) is the most promising display subsequently to LCD as we enter the 21st century. AM-OLED not only high-resolution and easy to achieving large area displays, in order to further develop the OLED technology, we can only resort to Active Matrix Driving. This paper researches the drive technology for amorphous silicon thin film transistor (a- Si TFT) AM-OLED, devises and make a driver model for 5-inch (320×240) color AM-OLED display based on the field digital grey scale technology. This paper introduces the concept of "anti-field" during the module design, we add controllable voltage to two pixel circuit public electrode and effectively restrain the irreversible shift of a-Si TFT threshold voltage; in the FPGA program design, we leave a part of space as the regional chip buffer memory in it, realize the dual buffer of the data signals, plus two external SRAM chips as regional chip buffer memory, the data signal was sent to screen through the triple buffer, this solve the slow pace problem brought about by the low rate of carrier mobility of the amorphous silicon thin film transistor. In addition, two SRAM work under parallel mode, thus significantly reduce the time spent in writing data into the OLED screen and improve the work efficiency of driver modules work. Simulation results show that fields signal correspond with the output data signal, verify that it can realize the display of the four gray in this display driver module. The realtime-test for the output signal of the driver IC and a color screen monochrome display shows that the drive module designed in this paper can drive a-Si TFT AM-OLED display.