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PubMed · 11410389

A single supply biopotential amplifier.

E M Spinelli·N H Martinez·M A Mayosky
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Abstract

A biopotential amplifier for single supply operation is presented. It uses a Driven Right Leg Circuit (DRL) to drive the patient's body to a DC common mode voltage, centering biopotential signals with respect to the amplifier's input voltage range. This scheme ensures proper range operation when a single power supply is used. The circuit described is especially suited for low consumption, battery-powered applications, requiring a single battery and avoiding switching voltage inverters to achieve dual supplies. The generic circuit is described and, as an example, a biopotential amplifier with a gain of 60 dB and a DC input range of +/-200 mV was implemented using low power operational amplifiers. A Common Mode Rejection Ratio (CMRR) of 126 dB at 50 Hz was achieved without trimming.

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Amplifiers, ElectronicElectric ImpedanceElectric Power SuppliesElectrocardiographyEquipment DesignSignal Processing, Computer-AssistedTechnical ReportJournal Article

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BibTeXRIS

E M Spinelli, N H Martinez, M A Mayosky. 2001. A single supply biopotential amplifier.. https://doi.org/10.1016/s1350-4533(01)00040-6

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