VLSI potentiostat array with oversampling gain modulation for wide-range neurotransmitter sensing

Milutin Stanaćević, Kartikeya Murari, Abhishek Rege, Gert Cauwenberghs, Nitish V. Thakor

Research output: Contribution to journalArticle

Abstract

A 16-channel current-measuring very large-scale integration (VLSI) sensor array system for highly sensitive electrochemical detection of electroactive neurotransmiters like dopamine and nitric-oxide is presented. Each channel embeds a current integrating potentiostat within a switched-capacitor first-order single-bit delta-sigma modulator implementing an incremental analog-to-digital converter. The duty-cycle modulation of current feedback in the delta-sigma loop together with variable oversampling ratio provide a programmable digital range selection of the input current spanning over six orders of magnitude from picoamperes to microamperes. The array offers 100-fA input current sensitivity at 3.4-μW power consumption per channel. The operation of the 3 mm × 3 mm chip fabricated in 0.5-μm CMOS technology is demonstrated with real-time multichannel acquisition of neurotransmitter concentration.

Original languageEnglish (US)
Pages (from-to)63-72
Number of pages10
JournalIEEE Transactions on Biomedical Circuits and Systems
Volume1
Issue number1
DOIs
StatePublished - Mar 1 2007

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Keywords

  • Biomedical instrumentation
  • Correlated double sampling
  • Current measurement
  • Micropower techniques
  • Potentiostat
  • Sigma-delta modulator
  • Switched-capacitor circuits

ASJC Scopus subject areas

  • Biomedical Engineering
  • Electrical and Electronic Engineering

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