1-V low-power high-accuracy CMOS potentiostat circuit for amperometric sensor

This paper describes the design of a low-power low-voltage potentiostat circuit in a 0.18-μm CMOS technology. Current-based technique is used and high accuracy is achieved by using a wide swing current mirror with negative feedback loops. Low power dissipation was achieved by cleverly sharing operational amplifiers for two negative feedback loops simultaneously, thus the number of operational amplifiers is reduced to two. Bulk-driven input technique is used to allow operational amplifier to operate with low power dissipation and low power supply voltage. Simulation results showed that the circuit exhibits the maximum error of 0.05% and an output linear regression of R²=0.99996, while operating under a single 1-V power supply voltage. The maximum power dissipation is 12.3 μW with the maximum sensor current of 6 μA.