一种有源有机发光显示屏(AM-OLED)驱动电路的设计

A Driving Circuit Design for Active Matrix Organic Light Emitting Diode Display

介绍一种有源有机发光显示屏(AM OLED)的驱动电路的设计方法。像素驱动电路采用常用的两管电路结构,依据此像素驱动电路,提出一种利用多晶硅TFT将部分外围驱动电路集成于衬底的设计方法和电路结构。采用互补的多晶硅TFT管设计屏上移位寄存器,传输门等模块,将部分外围驱动电路集成于OLED显示屏的衬底上,极大地减小了数据信号线的数目,降低了屏内信号线布线和屏外驱动电路的复杂程度。进一步讨论了利用复杂可编程逻辑器件(CPLD)设计驱动AM OLED显示屏专用集成芯片的设计方案。

In this paper, the driving circuit design was introduced for active matrix organic light emitting diode display, the pixel electrode circuit was discussed. And the method was proposed for some peripheral integration of driving circuits on substrate using complementary poly-silicon thin film transistor (TFT) to reduce the lead lines between the OLED display and peripheral circuitry, and simplify the peripheral driving complexity. Based on the two-TFT pixel electrode circuit, we design the driving circuit on the panel. Firstly a kind of shift register circuit structure was given, and using this circuit and some accessory gate circuits the gate driver was composed for the scan lines. Further the data sampling circuit on panel was constructed. For reduce the connection lines with the peripheral driver, the data lines were divide into M blocks. When the gate bus line is enabled, the blocks are in operation one by one. Consequently the analog signal from the peripheral driver will transmit to the data lines. This data voltage is applied on the two-TFT pixel circuit to drive the OLED. Because the data voltage is different analog signal, the OLED current is different as the data voltage and its luminance change with the OLED current. By AIM-Spice software we simulate the driver integrated on the panel, and verify the gate driver and data sample circuit function. A specific programmable application specific driver IC design was proposed for active matrix organic light emitting diode display, it is achieved by using CPLD (Complex Programmable Logic Device) chip. We make use of the hardware description language VHDL to program the CPLD and generate the external control signal for active matrix OLED panel. And at the same time CPLD operates the data process and outputs the digital display data with grey scale, those digital data were converted to analog voltage signal and transmitted to data sampling circuitry on panel. Our design results were verified by simulation and synthesis. At last the outline of the specific application IC and OLED display was shown.