Multi-Site Impedance Measurement System based on MAX30001 Integrated-Circuit

Abstract

In this work, the accuracy of the MAX30001 integrated-circuit for impedance measurements is characterized using measurements of resistors and 2R-1C configurations with |Z| <; 200Ω in the frequency band from 1 kHz to 128 kHz. Measurements were collected using a prototype system that integrated analog multiplexors to enable measurements of up to 4 test impedances by routing the MAX30001 excitation/measurement signals to multiple sites without manual switching. The additional analog switching circuitry did not degrade the MAX30001 measurements. Using a two-point calibration for the MAX30001 reduced the error of resistance measurements from a maximum of 4.29% to <; 0.22%, but measurements of complex impedances showed significantly higher errors which require further investigation to identify the source of errors and implement methods to correct.