An Enhanced Measurement Circuit for Piezoresistive Pressure Sensor Array

Abstract

A measurement approach of resistive sensor arrays has posed more obstacles than in single point resistive sensors. The effect of a crosstalk current in the array is the main factor that results in an inaccurate resistance scanning. In the application of pressure sensors, the presence of crosstalk current will cause ghost images on the area where no actual force is exerted onto the sensor array. In this paper, the enhanced measurement circuit has been specifically designed based on the zero potential circuit method to overcome the crosstalk error for improved accuracy. PSPICE simulation results on the 5×5 resistive array showed improved accuracy compared to the previous voltage dividing measurement approach, with the error reducing from 12.987% to 1.191%.