A Fully Differential Potentiostat

Low-voltage, single-ended (SE) potentiostats are unable to detect many analytes of interest because the oxidation potentials of these analytes are greater than the voltage that the potentiostat can deliver to the electrodes. In this work, a fully-differential (FD) potentiostat is described which enables detection of a wide range of analytes using a supply voltage of 1.8 V. The FD potentiostat was implemented in TSMC's 0.18 mu m CMOS process and has been verified experimentally. A theoretical discussion of the FD potentiostat is given and comparisons to SE potentiostats; are provided. Biological and environmental analytes are chemically detected using the FD potentiostat.