title: Design of a wideband CMOS impedance spectroscopy ASIC analog front-end for multichannel biosensor interfaces.
abstract: This paper presents the preliminary design and simulation of a flexible and programmable analog front-end (AFE) circuit with current and voltage readout capabilities for electric impedance spectroscopy (EIS). The AFE is part of a fully integrated multifrequency EIS platform. The current readout comprises of a transimpedance stage and an automatic gain control (AGC) unit designed to accommodate impedance changes larger than 3 order of magnitude. The AGC is based on a dynamic peak detector that tracks changes in the input current over time and regulates the gain of a programmable gain amplifier in order to optimise the signal-to-noise ratio. The system works up to 1 MHz. The voltage readout consists of a 2 stages of fully differential current-feedback instrumentation amplifier which provide 100 dB of CMRR and a programmable gain up to 20 V/V per stage with a bandwidth in excess of 10MHz.
authors.forename: Virgilio
authors.initials: V
authors.lastname: Valente
authors.lastname: Dai Jiang
authors.forename: Andreas
authors.initials: A
authors.lastname: Demosthenous
mesh_terms: D000669:Amplifiers, Electronic; D015374:Biosensing Techniques; D058266:Dielectric Spectroscopy; D004867:Equipment Design; D012815:Signal Processing, Computer-Assisted