High-power laser diodes can be used directly as lasers or as pump sources for amplifiers.

Laser diode LD driver instructions:

1. Constant current drive: Due to the volt-ampere characteristics of the diode, the conduction voltage at both ends is relatively less affected by changes in current, so it is not suitable for voltage sources to drive laser diodes. DC constant current is required to drive laser diodes. When used as a light source, the driving current is generally ≤500mA. When used as a pump source, the driving current is usually about 10A.
2. ATC control (automatic temperature control): The threshold current of the light source, especially the laser, will change with changes in temperature, which will cause the output optical power to change. ATC acts directly on the light source, making the output optical power of the light source stable and not affected by sudden changes in temperature. At the same time, the wavelength spectrum characteristics of laser diodes are also affected by temperature. The wavelength spectrum temperature coefficient of FP laser diodes is usually 0.35nm/℃, and the wavelength spectrum temperature coefficient of DFB laser diodes is usually 0.06nm/℃.For details, see the basics of fiber-coupled semiconductor lasers. The temperature range is generally 10~45℃. Taking the butterfly package as an example, pins 1 and 2 are thermistors to monitor the temperature of the laser tube, usually 10K-B3950 thermistors, which feed back to the ATC control system to drive the TEC cooling chip on pins 6 and 7 to control the temperature of the laser tube. , forward voltage cooling, negative voltage heating。