A low-power, offset-corrected potentiostat for chemical imaging applications

Traditional potentiostat designs often focus on high accuracy using high precision discrete components and often involve a limited number of discrete electrodes. Modern medicine and biological research require the use of high-density biosensor arrays to gain a better understanding of cellular communication in biological systems. Such applications involves hundreds or thousands of electrodes on a single silicon substrate. Each set of electrodes is supported by an independent group of circuits to allow real-time, multichannel detection and characterization of bio-signals. This paper presents a low power, offset-calibrated potentiostat design in a commercial 0.18um CMOS process for use in single-chip biosensor array applications to generate high resolution chemical images. The design uses a reusable on-chip calibration circuit to reduce amplifier offset error, with 40.3 μW of power consumption and a total silicon area of .02 mm².