The Influence Mechanism and Improvement Strategy of Multiplexer on Measurement Error of the 2-D Resistive Sensor Array Data Acquisition Circuit

The multiplexer plays a crucial role in the scanning process of resistive sensor arrays for data acquisition. It is, however, important to note that the on-resistance of the multiplexers can impact the accuracy of the measurement results for the specific element being tested (EBT). This limitation can hinder the integrated application of resistive sensor arrays. Aiming at the typical resistive sensor array data acquisition circuit, such as the zero potential method (ZPM) and voltage feedback method (VFM), this article systematically analyzes the influence of the on-resistance of the multiplexer on the measurement error. First, the mathematical models of the on-resistance of the multiplexer and the measurement error of the EBT have been established. Additionally, improved strategies for reducing the measurement error from the multiplexer have been proposed. The simulation results in Proteus not only confirm the correctness of the influence mechanism analysis but also demonstrate that the improved strategies can minimize measurement errors caused by the multiplexer under different cases. Finally, the actual circuit based on the improved strategy has been implemented, and the corresponding experimental results show that the actual 2-D resistive sensor array data acquisition circuit has excellent measurement accuracy (below 0.3%) and shape accuracy, and further, it can accurately identify the pressure of the piezoresistive sensor array. The improvement strategies proposed in this article offer highly precise scanning techniques for large-scale resistive sensor arrays.