A Low-Cost Integrated Approach for Balancing an Array of Piezoresistive Sensors for Mass Production Applications

Offset error is inherently present in piezoresistive sensors. This is caused by a heterogeneous excitation response and static resistance of different sensing elements. Such an error makes applications with multiple sensors difficult because a proper calibration or normalization scheme is desired. A low-cost integrated approach which can provide a closed form mathematical solution for normalizing an array of piezoresistive sensors is presented in this paper. The proposed solution just needs a few external resistors and hence is most suitable for mass commercial applications. Necessary and sufficient conditions to derive the solution are considered. This technique could be used offline so that the sensors array could be used directly after going through the normalization procedures.