基于结型场效应管开关特性控制 AC-LED晶粒分段导通的研究

摘要

In order to improve the light source utilization rate , we design a circuit of AC-LED grains segmented conduction controlled by Junction Field-effect Transistor . By designing circuit model and optimizing parameters , The Jfet switch respond speed and saturation time are increased . And also, saturation current is obviously controlled .We divide AC-LED grains into groups with lower forward voltage . The effect is achieved that each group of LED grains controlled by Jfet turn on earlier with constant current . The simulation result shows that the turn-on time of AC-LED controlled by Jfet reaches 90%, meanwhile the turn-on time of AC-LED without the control of Jfet is 40%in a cycle .%为了提高AC－LED光利用率，本文设计了一种利用结型场效应管开关特性控制AC－LED中阵列晶粒分段提前导通的电路。利用Pspice软件设计了电路模型，优化了结型场效应管参数，提高了场效应管的开关响应速度、饱和工作时间以及控制了饱和电流值。对LED晶粒分组，降低了LED晶粒开启电压。得到了场效应管依次控制各组LED晶粒提前、恒流导通的效果。仿真结果表明：利用结型场效应管控制AC－LED分段导通，每个周期的导通时间由未加场效应管的40％提高到了90％。