Low power CMOS potentiostat for three electrodes amperometric chemical sensor

This paper presents two front-end electronics architectures, called potentiostats, developed for measuring gas concentrations with electro-chemical sensors. These potentiostats are designed to be integrated in wireless embedded systems. Consequently, the total power consumption is critical. An amperometric three-electrodes electro-chemical sensor has been chosen since it is powerless. Its electrical model has been determined in order to optimize the readout electronics associated. Two potentiostats have been realized in a 0.35μm CMOS process. The most power consumption optimized architecture designed in this work presents a consumption of 10.8μW over a range of detection included from 70nA to 25μA.