Amplifiers for bioelectric events: A design with a minimal number of parts

  • A. C. MettingVanRijn
  • A. Peper
  • C. A. Grimbergen


A design for an amplifier for bioelectric events is presented that has fewer parts than conventional designs. The design allows the construction of amplifiers of a high quality in terms of noise and common mode rejection, with reduced dimensions and with a lower power consumption. Gain, bandwidth and number of channels are easily adapted to a wide range of biomedical applications. An application example is given in the form of a multichannel EEG amplifier (gain is 20000), in which each channel consists of three operational amplifiers (one single and one dual), six resistors and two capacitors. The equivalent input noise voltage and current are 0.15 μVrms and 1 pArms, respectively, in a bandwidth of 0.2–40 Hz, and a common mode rejection ratio of 136 dB is achieved without trimming.


Common mode rejection ratio DC suppression Instrumentation amplifier Number of parts Recording of bioelectric events 


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Copyright information

© IFMBE 1994

Authors and Affiliations

  • A. C. MettingVanRijn
    • 1
  • A. Peper
    • 1
  • C. A. Grimbergen
    • 1
  1. 1.Department of Medical Physics & InformaticsUniversity of Amsterdam, Faculty of MedicineAmsterdamThe Netherlands

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