基于AD7710的热量计精密测温电路设计

Design of Precise Temperature Measuring Circuit of Calorimeter Based on AD7710

介绍了一种基于AD7710芯片的高精度热量计测温电路设计。该测温电路是通过采集惠斯顿桥路电势后差分放大,再充分利用AD7710可编程增益、系统校正、低通滤波、高精度模数转换等优势设计了测温电路,并给出软件分析流程图。经试验测试,该电路测温范围为0~45℃,分辨力为0.000 1℃,线性误差为±0.007%,稳定性为0.001 2℃,满足设计要求。

This paper introduces the design of a high precise calorimeter temperature measuring circuit based on AD7710 chip. The electrical potential of Huygens bridge is collected and differential amplified. The AD7710 with the programmable gain, system correction, low-pass filtering, high precise analog-to-digital conversion and other advantages is fully utilized to design the temperature measuring circuit. The flow chart of the software analysis is given. After the test, the circuit can measure the temperature ranging within 0 ~ 45 ℃, and has the resolution of 0.000 1 ℃, the linear error±0.007% and the stability of 0.001 2 ℃, which satisfies the design requirements.