A High-Precision Circuit-Simulator-Compatible Model for Constant Phase Element Using Rational Function Approximation

Constant phase elements (CPEs) are commonly used in bioelectronic systems, to model the impedance of bioelectrodes and electrode-electrolyte interfaces. To simulate systems with an electronic design automation tool, a circuit-simulator-compatible CPE is required use circuit simulation. This paper applies rational function approximation CPEs as frequency, which able be implemented Verilog-A language. In comparison previously published works simply approximate into several serially connected RCs, our work illustrates theoretical basis behind RCs provides method perform approximation, thus resulting smaller relative root mean square error magnitude (4 orders lower using 25 RCs) within bounded frequency range. validate accuracy, it applied modeling human cochleae, simulated results correlating well measured results. Furthermore, this that includes bioelectrode thin-film transistor switch, showing capability for simulation CPEs.