An Affordable Multichannel Potentiostat with 128 Individual Stimulation and Sensing Channels

Abstract

(Bio)electrochemical reactions are a promising, environmentally friendly alternative for many chemical processes. These processes, however, are known to be slow in time, to be strongly dependent on the environment and to vary between different samples. This necessitates research on studying optimal operating conditions of the (bio)electrochemical cells. Yet, current experiments have to rely on slow, sequential tests. To overcome these, this work proposes a potentiostat with 128 parallel channels to speed up research experiments. The 128-channel potentiostat makes extensive use of time-sharing and is implemented with PCB technology resulting in a cost-per-channel of only 5$, 4x lower than the state-of-the-art (SotA) and an area-per-channel of ≈ 93 mm2, 5x lower than the SotA. Realtime digital compensation of each individual channel is used to obtain a channel-to-channel mismatch below 1%. A cyclic voltametry experiment on all channels simultaneously illustrates the low channel-to-channel mismatch. A chronoamperometry experiment with 128 different potential steps in parallel illustrates the 128x experiment speedup.