基于PSpice的半导体激光高频调制系统设计

摘要

为了实现高频率的调制激光输出,设计了一种驱动系统由信号放大、电流调制、过流保护和具有慢启动功能的直流偏置电路高度集成的半导体激光高频调制系统.此系统采用了结构简单的直接调制方式,运用线性调频的高频信号去控制半导体激光器发射激光的强度,从而实现高频调制.在运用OrCAD/PSpice对高频调制驱动系统进行模拟仿真的基础上,最终研制出的半导体激光高频调制系统实现了频率为40.02 MHz、直流偏置为493.326mA、正弦波调制电流峰峰值为850mA的高频调制输出,调制激光平均功率为300mW.%In order to output high frequency modulation,we designed a high frequency modulation system of semiconductor laser which is composed of a signal magnifying circuit,a current modulation circuit,an over current protection circuit and a DC bias circuit with slow start function.The high frequency modulation drive system of semiconductor laser uses a simple structure of the direct modulation method.The direct modulation method controls intensity of semiconductor laser by a signal of adjustable frequency.We simulated the high frequency modulation drive system of semiconductor laser by OrCAD/Pspice.The high frequency modulation system of the semiconductor laser can output laser with frequency of 40.02 MHz and average laser power of 300 mW,and it can output modulation current with DC bias of 493.326 mA and peak value of sine wave modulation of 850 mA.