Article

A fully differential CMOS potentiostat

Dept. of Electr. Eng., California Inst. of Technol., Pasadena, CA, USA
05/2009; DOI: 10.1109/ISCAS.2009.5118228
Source: IEEE Xplore

ABSTRACT A CMOS potentiostat for chemical sensing in a
noisy environment is presented. The potentiostat measures bidirectional
electrochemical redox currents proportional to the
concentration of a chemical down to pico-ampere range. The fully
differential architecture with differential recording electrodes
suppresses the common mode interference. A 200μm×200μm
prototype was fabricated in a standard 0.35μm standard CMOS
technology and yields a 70dB dynamic range. The in-channel
analog-to-digital converter (ADC) performs 16-bit current-tofrequency
quantization. The integrated potentiostat functionality
is validated in electrical and electrochemical experiments.

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