大功率半导体激光器用电流源设计

摘要

Laser diode is a current injected device and the performance of current supply has great impact on the char-acteristic and life of LD.A current supply for high power LD is designed by the chip LT3755,and the output current can be changed continuously from 3.3A to 5.6A.When the output current is 4.5A,the current variation obtained in an experiment within 3 hours are smaller than 2mA,and the current stability is 4 ×10 -4 .In addition,the power supply has also some good features such as undervoltage protection,overvoltage,overcurrent,soft startup and other functions.%半导体激光器是一种电流注入式发光器件，驱动电流源的性能优劣对其工作特性和使用寿命有着很大的影响。本文利用芯片LT3755设计了一种大功率LD电流源，电流在3.3～5.6 A连续可调。当输出电流为4.5 A时，连续工作3 h内电流变化量小于2 mA，电流稳定度达到4×10-4。此外，该电源还具有欠压保护、过压保护、过流保护和缓启动等多种功能。