传感器信号采集电路启动时标度因数补偿研究

Research of scale factor compensation for signal acquisition circuit of sensor at start-up period

针对传感器信号采集电路启动阶段温度变化剧烈,温度场分布不均,从温度传感器获得的温度不准确的问题,研究了用电路启动阶段的校准标度因数代替温度,进而对电路标度因数进行温度补偿的方法。电路启动阶段的校准标度因数从校准电压得到,该标度因数紧随各器件温度的变化。同时电路标度因数与温度呈对应关系,可以得到启动阶段校准标度因数与电路标度因数的关系式。根据上述关系式和启动阶段的校准标度因数补偿电路标度因数。实验结果表明:用启动阶段的校准标度因数补偿后,电路标度因数在30℃内的重复性得到显著改善,这为传感器信号采集电路在多变温度环境下的快速启动提供了一种方法。

Aiming at the problem that temperature directly acquired from the temperature sensor is not accurate because of the violently varying temperature and the uneven temperature field distribution of sensor signal acquisition circuit at start-up period,a method that replaces the temperature with calibration scale factor at start-up period of the circuit is presented and then compensates the circuit scale factor.The calibration scale factor is acquired from calibration voltage at start-up period.The calibration scale factor follows the temperature change of each components.Circuit scale factor corresponds to temperature,so the relation expression between calibration scale factor and circuit scale factor at start-up period can be got.Compensate the circuit scale factor according to the above expression just mentioned and the calibration scale factor at start-up period.The experimental result indicates that after compensation with calibration scale factor at start-up period,repeatability of circuit scale factor in the range of 30 ℃ is improved remarkably,which provides a method for sensor signal acquisition circuit fast start-up in temperature-changeful environment.