Medical & Biological Engineering & Computing

, Volume 46, Issue 6, pp 613–619

Bootstrapped two-electrode biosignal amplifier

  • Dobromir Petkov Dobrev
  • Tatyana Neycheva
  • Nikolay Mudrov
Technical Note


Portable biomedical instrumentation has become an important part of diagnostic and treatment instrumentation. Low-voltage and low-power tendencies prevail. A two-electrode biopotential amplifier, designed for low-supply voltage (2.7–5.5 V), is presented. This biomedical amplifier design has high differential and sufficiently low common mode input impedances achieved by means of positive feedback, implemented with an original interface stage. The presented circuit makes use of passive components of popular values and tolerances. The amplifier is intended for use in various two-electrode applications, such as Holter monitors, external defibrillators, ECG monitors and other heart beat sensing biomedical devices.


ECG amplifier Common mode impedance Differential mode impedance Bootstrap feedback CMRR 


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Copyright information

© International Federation for Medical and Biological Engineering 2008

Authors and Affiliations

  • Dobromir Petkov Dobrev
    • 1
  • Tatyana Neycheva
    • 1
  • Nikolay Mudrov
    • 1
  1. 1.Centre of Biomedical Engineering “Ivan Daskalov”, Bulgarian Academy of SciencesAcad. G. Bonchev str.SofiaBulgaria

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