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PubMed · 16594298

Simple two-electrode biosignal amplifier.

D Dobrev·T Neycheva·N Mudrov
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Abstract

A simple, cost effective circuit for a two-electrode non-differential biopotential amplifier is proposed. It uses a 'virtual ground' transimpedance amplifier and a parallel RC network for input common mode current equalisation, while the signal input impedance preserves its high value. With this innovative interface circuit, a simple non-inverting amplifier fully emulates high CMRR differential. The amplifier equivalent CMRR (typical range from 70-100 dB) is equal to the open loop gain of the operational amplifier used in the transimpedance interface stage. The circuit has very simple structure and utilises a small number of popular components. The amplifier is intended for use in various two-electrode applications, such as Holter-type monitors, defibrillators, ECG monitors, biotelemetry devices etc.

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Amplifiers, ElectronicElectrocardiographyElectrodesElectrodiagnosisElectronics, MedicalEquipment DesignHumansModels, BiologicalJournal Article

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BibTeXRIS

D Dobrev, T Neycheva, N Mudrov. 2005. Simple two-electrode biosignal amplifier.. https://doi.org/10.1007/bf02430949

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