Temperature control circuit design of high-precision laser diode based on type III compensation network

Abstract

Since the performance of laser diodes is sensitive to ambient temperature, thermoelectric cooler temperature control circuits based on standard PID temperature compensation networks are usually designed to achieve diode constant temperature control. The thermoelectric cooler time constant and thermistor thermal time constant introduced in the temperature control system will reduce the stability margin of the system. In view of this, this paper designed a high-precision laser diode temperature control circuit based on the type III compensation network, and established the transfer function model, optimized the compensation network parameter tuning method, made the phase margin of the temperature control system reach π/8, and the long-term temperature control accuracy was better than 3 mK in the ambient temperature range of 5 to 40 C.