Non-Linear Modeling and Analysis of Amplifier-Less Potentiostat Architectures

Abstract

In this article, a previously published amplifier-less potentiostat architecture is further examined. Starting with a linearized model, the impact of the most important parameters is studied taking in account the electrodes-solution electrochemical interface. A detailed model is obtained and thoroughly verified, and recommended operating conditions are given for certain limit load conditions. Then, a more complete non-linear model is developed to take in account the measurement uncertainty introduced by the circuit non-linear components. This non-linear model is compared to a time domain description of the circuit and it is verified that it can predict the non-linear behavior with a precision better than 20%. This result enables the circuit designers to compensate for these effects and ultimately reduce the overall measurement uncertainty.