基于单片机的微球腔温度控制系统的设计  

Designed of Temperature Control System for Microsphere Cavity Based on SCM

作　　者：侯进旺[1] 冯欣悦[1] 化雪荟[1] 

机构地区：[1]佛山职业技术学院电子信息系,广东佛山528000

出　　处：《电子器件》2016年第4期768-773,共6页Chinese Journal of Electron Devices

摘　　要：设计了基于ADS1247的铂电阻测温方案,将ADS1247输出的可编程恒定电流作为铂电阻激励源,并采用ADS1247集成的可编程放大器放大铂电阻的电压降,然后将放大器输出的信号进行24 bit模数转换。升降温通过BTS7960驱动芯片构成的半桥电路分别驱动加热片和制冷片。在控制策略上选用增量式数字PID算法,单片机ATmega128进行控制量计算,输出PWM信号控制驱动电路。电路结构简单,测量精度及稳定性好。软件上采用零点调准、查表和线性插值法进一步实现温度的精密测量。经长时间实验观测,测量误差在0.02℃内,系统温度控制精度优于0.1℃。The platinum resistance temperature program is designed based on the ADS1247. The constant current in the ADS1247 which is programmable drives the RTD （Real Time Differential）. Then, the PGA （Programmable Gain Amplifier）in the ADSl247 amplifies the voltage on the RTD. At last, the 24-Bit analog-to-digital converter converts the PGA＇s output. Heating and cooling through BTS7960 half bridge circuit control the temperature. The microcontroller ATmega128 calculates the controlling amount by using incremental digital PID （Proportion Integration Differentiation） algorithm, outputs the PWM signal to control the drive circuit. The circuit structure is simple with precious measurement and good stability. Software adopts zero alignment, table lookup and linear interpolation method to further realize the precision of temperature measurement. By the experimental observation for a long time, measurement error is within 0.02 ℃ and the system temperature control precision is better than 0.1 ℃.

关 键 词：单片机 温度控制 精密测温 PID控制 

分 类 号：TN791[电子电信—电路与系统]