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PubMed · 10612904

A transconductance driven-right-leg circuit.

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

Biopotential measurements are very sensitive to electromagnetic interference (EMI). EMI gets into the acquisition system by many ways, both as differential and common mode signals, driven-right-leg circuits (DRL) are widely used to reduce common mode interference. This paper reports an improvement on the classic DRL. The proposed circuit uses a transconductance amplifier to drive the patient's body. This configuration has some interesting properties, which provide an extended bandwidth for high-frequency EMI rejection (such as fluorescent lights interference). The improvement is around 20 dB for frequencies of few kilohertz and the circuit is easy to compensate for stability. A comparative analysis against a typical DRL is presented, the results obtained have been experimentally tested.

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BibTeXRIS

E M Spinelli, N H Martínez, M A Mayosky. 1999. A transconductance driven-right-leg circuit.. https://doi.org/10.1109/10.804574

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