基于半导体致冷器的高精度PWM功率驱动器

在大功率半导体激光器(LD)的温度控制系统中，针对其控温执行器件半导体制冷器的驱动特性，设计了一种基于单片机的高精度脉宽调制(PWM)功率驱动器。以89C51单片机为控制核心，采用12bit的D／A转换器，确保了整个系统具有较高的控制精度。采用切换D／A基准电压的方法解决了扩大系统动态范围与提高控制精度之间的矛盾，提高了系统的性能价格比。提出了一种防止MOSFET H-桥桥臂“直通”现象的新型电路“D触发器-阻滞延迟电路”。输出电压误差率为0．4％。

High Precision PWM Power Amplifier Based on Thermoelectric Cooler

In the system of temperature control of high-power semiconductor laser(LD),a high-precision pulse width modulation(PWM) power amplifier was designed based on the characteristics of temperature controller(thermoelectric coolers) by using single chip micro-computer.With the single chip micro-computer 89C51 as the central controller and 12 bit D/A converter,the system gained higher control accuracy.The conflict between dynamic range enlargement and controlling precision improvement was eliminated with the method of DAC norm voltages switching,and so,better cost-performance can be achieved.A new circuit D trigger-block delay circuit was also put forward to prevent MOSFET H-bridge arms from cross-connection.The output voltage error is 0.4%.