Design of high frequency modulation system of semiconductor laser based on PSpice

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.