基于555时基电路的测温系统设计

介绍了一种以555时基集成电路和单片机构成的数字化温度测量电路及其工作原理。利用负温度系数热敏电阻PT100测量外界温度，通过555定时器构成的V／F转换器将温度传感器的阻值转换成脉冲信号，采用单片机的计数器测量脉冲信号，由查表法得到实际温度值，从而实现温度测量。提供了单片机的定时器／计数器的工作方式，给出了单片机温度测量的软件流程图。该系统体积小，成本低，实际运行表明具有较高的测量精度和较强的抗干扰能力，可广泛应用于工业控制中。

Design of Temperature Measurement System Based on 555 Timing Circuit

This paper proposes a design concept of digital temperature measurement circuit based on 555 timing circuit and single chip microcomputer,which measures the temperature using PT100 sensor.Based on V/F converter circuit composed of 555 timing circuit,the resistance of sensor is converted into a pulsed signal,which is measured by the timer of single chip microcomputer.The actual temperature is obtained by table look-up technique to realize temperature measurement.This paper presents the working mode of timer/...