Digital Calibration for Current-Loop Output of Piezoresistive Sensors

The precision of piezoresistive sensors is low between wide temperature range .The conditioning result isn’t ideal by analog approaches. Also the efficiency is very low. To improve this condition , a digital approach is introduced. It coverts sensors’ analog signal to digital value, and then uses polynomial and coefficients stored in singlechip to correct the digital value. At last , the singlechip coverts corrected digital value to analog signal to output. Its conditioning principle and calibration process is also described. We realized 4-to-20mA-current-loop-output of piezoresistive sensors using this aprroch. Calibration results show this method is efficient and low cost.