The Design of Driving Circuit for Semiconductor Laser

Due to the susceptibility of semiconductor lasers to injection current and operating temperature, this study designs a high-precision and highly integrated constant current drive and constant temperature control system based on the STM32H7 series microcontroller.The constant current drive module adopts a voltage-controlled constant current source negative feedback circuit, achieving precise current regulation. The constant temperature control module selects the MAX1968 temperature control chip to drive the thermoelectric cooler(TEC), combined with an improved incremental PID algorithm, achieving a temperature control accuracy of $\pm 0.01^{\circ} \mathrm{C}$ within the range of $10^{\circ} \mathrm{C}$ to $40^{\circ} \mathrm{C}$. The system integrates overcurrent protection, soft start, anti-static, and reverse surge suppression circuits to ensure the long-term stable operation of the laser.