Design And Realization Of The High Power Pulsed LD Driver Circuit For Pumping Solid State Laser

Since the invention of the laser, it has become the absolutely necessary part of our daily life,industry, agriculture, military, aerospace or bio medical field over the past few decades in the1960s.The research on semiconductor laser in our country could cath up with the pace of foreign,but in the aspect of driving power, it is still gap behind compared with the developed countries,especially adjusting the pulse amplitude and width of driving current at the same time.Accordingto the needs, this paper aims at making a high-power, adjustable pulsed and current LD drivingpower.After analyzing the effects of temperature and current on the output characteristics ofsemiconductor lasers, combining with all indicators, considering the possibility of damages, thispaper presents a comprehensive design of semiconductor laser driver.The system includes powersupply circuit, current control, temperature control, system protection and GUI etc.The power supply circuit uses linear series regulator combining with switch buck regulatoraccording to different requirements.The MCU, STM32F103RCT6with12-bit DAC, was used asthe signal of current control. It adjusts the drive pipe,which is result comparison of the samplingcurrent and OP37, high speed and low noise operational amplifier. Then it controls the pulsewidth, duty cycle, repetition rate, and adjusts the output current amplitude.The current stability isbetter than0.5%, and the rising edge of the pulse is less than50ns.In the temperature control parts,it uses the sensor chip ADT7420to capture the temperature data. The H-bridge circuit based onthe digital PID algorithm drives the semiconductor refrigeration piece to control the temperatureof LD.It is safe with current surge,static electricity,overcurrent and overtemperature protection bycontrolling hardware circuit.The effect of the software and hardware double protection，prolongsthe service life of LD.At last, test the system performance, verify the feasibility of design. Using the power drivensemiconductor laser pulse808nm laser, the laser pumped Nd:YAG crystal composed of DPSSLsystem, combined with the intracavity frequency doubling,473nm blue laser.