摘要
针对常规分立双积分AD只能处理单端信号的问题,给出了一种输入和基准电压均支持差分信号的分立差分双积分AD;在热电阻测量中,把热电阻和基准电阻串联同一回路,以基准电阻压降作为基准,对热电阻的压降进行测量,并从软硬件两个方面对常见的误差因素进行对消处理;实验表明,该电路用于PT100测温时,跳字不超过0.1℃,精度可以达到±0.1℃,且对运放型号无特殊要求,是一种低成本、高精度的温度测量方案。
According to the discrete double integral AD circuit can only deal with single end input, an discrete differential double integral AD is proposed, which support difference signal both input and reference voltage. In RTD measurement, the RTD resistor and the reference resistor are connected in series in the same circuit, and measure the voltage on the thermal resistance using the voltage on reference resistor as a reference. For common errors, the circuit and the software make a cancellation processing. Experiments show that when the circuit is used for PT100, the jitter does not exceed 0. 1℃, precision can reach ±0. 1℃, and the op amp models does no special requirements. This is a low--cost, high--precision temperature measurement solutions.
出处
《计算机测量与控制》
2015年第4期1312-1315,共4页
Computer Measurement &Control
