自动气象温湿度传感器采集电路设计与实现

Design and implementation of acquisition circuit for automatic meteorological temperature and humidity sensor

为了顺应民航气象自动化发展需求,设计了一种自动气象温湿度传感器采集电路,能够实现对民用机场跑道周边温湿度要素的较高精度采集。系统对硬件电路部分进行了模块化结构设计,对温湿度采集原理进行了分析,利用4线制PT100铂电阻对温度进行测量,通过恒流源驱动的方式产生温度对应电压,再通过AD7792进行采集,计算出温度传感器的电阻值Rpt100。湿度信号输出类型为0~1 V的直流电压,利用AD7792的第2通道以及片内1.17 V的基准电压进行采集,得到ADSample2采样值,计算出湿度对应的电压值Vrh(单位:mV),Vrh在数值上与湿度采样值相等。试验证明采集电路可以完成对温湿度信号的采集。

In order to meet the needs of the development of civil aviation meteorological automation,an automatic meteorological temperature and humidity sensor acquisition circuit is designed,which can achieve high precision acquisition of temperature and humidity elements around the runway of civil airport.The hardware circuit of the system is designed with modular structure,and the principle of temperature and humidity acquisition is analyzed.The temperature is measured by 4-wire PT100 platinum resistance.The voltage corresponding to temperature is generated by constant current source driving.Then the resistance value Rpt100 of temperature sensor is calculated by AD7792.The output type of humidity signal is 0~1 V DC voltage.The second channel of AD7792 and the reference voltage of 1.17 V on-chip are used to collect the sample value of ADSample2.The voltage value Vrh(unit:mV)corresponding to humidity is calculated,and Vrh is equal to the humidity sampling value in value.Experimental results show that the acquisition circuit can complete the acquisition of temperature and humidity signals.