Design of Tunable Laser Drive and Temperature Control System Based on FPGA

Based on the operational principles of field-programmable gate arrays (FPGA) and laser diodes, we have designed and constructed a semiconductor laser driver circuit. The temperature control and feedback circuit employ high-speed MOSFETs as switching devices to drive the laser diodes. Utilizing LTspice simulation software, we analyzed the impact of supply voltage, energy storage capacitor, and damping resistor on the driving pulse in the laser driver circuit, ultimately selecting optimal circuit parameters. This circuit meets the design requirements for high-current nanosecond pulse semiconductor laser driver circuits. Through interaction with an upper computer system, it is possible to continuously adjust the laser's drive current and operating temperature to ensure that the output wavelength of the semiconductor laser falls within an optimal range. Following testing, this temperature-controlled semiconductor laser driver system fully satisfies practical application needs and effectively resolves issues related to unstable wavelength and power caused by fluctuations in the working temperature of the semiconductor laser.