A Digital Active Electrode System

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


This chapter presents a digital active electrode (DAE) system for multiparameter biopotential signal acquisition. Each DAE is built around an ASIC that performs analog signal processing and digitization by means of on-chip instrumentation amplifiers (IAs), a 12-bit ADC, and a digital interface. Via a standard two-wire I2C bus, up to 16 DAEs (15 channels) can be connected to a commercially available microcontroller, thus significantly reducing the system’s complexity and cost. At the circuit level, each DAE utilizes an innovative “functionally” DC-coupled amplifier for DC and extremely low-frequency biopotential signal measurements while still being AC-coupled. At the system level, a generic common-mode feedforward (CMFF) technique improves the CMRR of an AE pair from 40 dB to the maximum 102 dB.


Digital interface I2DC-coupled amplifier CMFF Multimodal 


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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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