Design Of Precise Temperature Controller And Direct Current Driver For Chaotics Semiconductor Laser

In recent years,chaotic signals have shown important applications in areas such as communications,sensing,and information security.At present,chaotic signals are generated in two main ways: first,discrete devices produce chaotic signals;second,chaotic lasers are integrated to generate chaotic signals.However,discrete devices produce chaotic signals,which have complex structures,are susceptible to environmental influences,and are unstable in output and are not conducive to the application of chaotic signals.As a new type of optoelectronic device,the integrated chaotic laser has the advantages of small size,easy integration of other systems,and the ability to output stable and reliable wide-band chaotic signals.It has become a research hotspot.The gain medium used by chaotic semiconductor lasers is gallium arsenide,indium phosphide and other materials,whose characteristics are very sensitive to temperature,and the temperature changes have an impact on the wavelength and threshold current of the chaotic semiconductor laser,and ultimately will result in the chaotic state of the laser output stable.The bias current has an important influence on the path of the laser into the chaos and the state of the output chaotic signal.Therefore,it is very important for the chaotic semiconductor laser to perform high-precision temperature control and DC driver control.At present,the temperature control source and driver source of existing lasers are relatively bulky and expensive,which is not conducive to system control and integration.Aiming at these problems,this paper designs a set of high-precision temperature control and DC driver circuit system for chaotic lasers.The system mainly includes three parts: temperature controller module,DC driver module,and host computer controller module.This article uses Analog Devices(ADI)company's high temperature precision chip ADN8830 as the main chip of the temperature control circuit,and design Wheatstone bridge temperature acquisition and conversion circuit,RC-based PID temperature compensation network,TEC control and power amplifier circuit,etc.The module constitutes a complete closed-loop temperature control structure.The DC driver module adopts ADN2830 as the main control chip,and combines the high-precision,dual-channel digital potentiometer AD5172 to precisely control the laser injection current.The host computer controller module constructs a hardware platform based on serial communication by calling the VISA node function in LabVIEW to realize the control of the circuit system.The main research content of this article is as follows:(1)A temperature-acquisition conversion circuit based on Wheatstone bridge method,a PID temperature compensation network based on RC,and a complete closed-loop temperature control structure composed of a TEC control and power amplification circuit are designed.The theory verifies the feasibility of the experimental scheme,and on this basis,Altium Designer software is used to draw the PCB diagram,and a temperature control module circuit for the high-precision temperature control and DC driver circuit system of the chaotic semiconductor laser is fabricated.Experiments show that the circuit system temperature control range is 18.09 °C ~ 42.02 °C,temperature control accuracy is up to 0.01 °C,fully meet the requirements of stable operation of chaotic semiconductor lasers.(2)The driver module based on the ADN2830 chip is designed.The AD5172 high-precision digital potentiometer AD5172 is used to design the series and resistor circuits to form a laser driver module.Based on this,a PCB diagram is drawn to create a high-level chaotic semiconductor laser.Accuracy temperature control and DC driver circuit system drive control module circuit.Experiments show that the circuit system current output range is about 0mA ~ 115.6mA,the current control accuracy is at least 0.01 mA,fully meet the requirements of stable operation of the chaotic laser.(3)A CMOS operational amplifier is used to amplify the driving current of the high-precision temperature control and DC driving circuit system of the chaotic semiconductor laser,and a semiconductor optical amplifier driving circuit is manufactured.Experiments show that the amplified drive circuit system current output range is about 0mA ~ 455.6mA,and the current control accuracy of the minimum is up to 0.01 mA,it can meet the semiconductor optical amplifier normal working requirements.(4)By calling the VISA node function in LabVIEW to build a hardware platform based on serial communication,a PC serial port communication data system is designed with the PC as the host computer and the minimum system of the STM32 microcontroller as the lower computer.it realizes the control of the host computer control to the circuit system and the data processing function.Through Lab VIEW graphical programming software interface development and the corresponding function to achieve.Experimental verification shows that the software runs stably in accordance with the experimental requirements.