Review of Bio-Amplifier Architectures

  • Jiawei Xu
  • Refet Firat Yazicioglu
  • Chris Van Hoof
  • Kofi Makinwa
Part of the Analog Circuits and Signal Processing book series (ACSP)


Biopotential amplifiers (or simply bio-amplifiers) are the most critical building blocks of an EEG readout circuit. This is because they constitute its first stage and so largely determine its noise level, input impedance, and CMRR. This chapter presents an overview of state-of-the-art bio-amplifiers that can be used as AEs for wearable EEG acquisition. Furthermore, this chapter also discusses the advances and drawbacks of different IA architectures and describes several circuit techniques to optimize critical specifications such as noise level, input impedance, electrode offset tolerance, CMRR, and power dissipation.


Instrumentation amplifier EEG readout Electrode offset Input impedance CMRR 


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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  • Jiawei Xu
    • 1
  • Refet Firat Yazicioglu
    • 2
  • Chris Van Hoof
    • 3
  • Kofi Makinwa
    • 4
  1. 1.Holst Centre / imecEindhovenThe Netherlands
  2. 2.Galvani BioelectronicsStevenageUK
  3. 3.ESAT-MICASKU Leuven / imecLeuvenBelgium
  4. 4.Delft University of TechnologyDelftThe Netherlands

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