作　　者： ; ; ;

机构地区： 吉林大学通信工程学院

出　　处： 《发光学报》 2002年第5期518-522,共5页

摘　　要： 利用AIM Spice对有源OLED显示器的两管TFT像素驱动电路进行了仿真分析 ,结果表明合理选择电路参数 ,能够保证OLED显示器的亮度要求 ,并在一帧时间里保持恒流 ,改变数据电压能够调整OLED显示器的灰度级 ;给出了电路中各类参数变化对电路性能的影响 ;在此基础上 ,得到了两管TFT像素驱动电路各参数的选择参考值。为OLED显示器像素驱动电路结构的设计、参数选取。 Two TFT pixel driving circuit was simulated and analyzed for Active Matrix OLED using AIM Spice in this paper.From the simulation results,the influences of the driving transistor T\-2 W/L ratios on the OLED current were shown.For a typical OLED emission efficiency,and a known pixel area,a current level is needed to achieve the pixel brightness.By the simulation results,reasonable T\-2 W/L ratios can be obtained.The simulation results also showed that the OLED grayscale could be adjusted by changing the data voltage.On the other hand,the source voltage should be high enough to ensure the T\-2 operates the saturation state.Further more,the two TFT pixel electrode circuit transient characteristic was simulated.The impact of the T\-1 W/L ratios and storage capacitor on output characteristic was discussed.The lower size capacitor will reduce the OLED current during the pixel electrode OFF period.And too large capacitor will deduce a large charge time constant,which impacts on the respond speed and brightness of OLED.The larger T\-1 W/L ratios will also result in the drop of the OLED current during the pixel electrode OFF period.So they need to be carefully selected.From the transient characteristic of the influences of the value of scan pulse voltage on output current,it is clear that the lower scan voltage value will result in the OLED current is not proportional to data voltage .Thus the OLED brightness cannot follow the variation of the data voltage .The increasing of scan voltage value will solve the above problem. Form the temperature characteristic,the two TFT pixel driving circuit cannot overcome the effect on OLED current because of the shift of threshold of the driving TFT due to the manufacturing variations and the circuit aging. The simulation results indicate that if the parameters are chosen properly,driving circuit can ensure the OLED brightness requirement and the constant output current in a frame time,and the grayscale can be adjusted by changing

关 键 词： 像素驱动电路 有源 仿真分析 显示器 有机 高分子电致发光器件

领　　域： [电子电信] [电子电信]