Capacitive driven-right-leg circuit design

Capacitive electrodes allow to pick-up biopotentials through a dielectric layer, without using electrolytes. However, this technique is vulnerable to electric-field interference, mainly to common mode voltages produced by the 50 Hz power-line. A fully Capacitive Driven Right Leg (CDRL) circuit is pr...

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Detalles Bibliográficos
Autores: Haberman, Marcelo Alejandro, Spinelli, Enrique Mario, Arias García, Pablo Andrés, Guerrero, Federico Nicolás
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/53757
Acceso en línea:http://hdl.handle.net/11336/53757
Access Level:acceso abierto
Palabra clave:Biomedical
Biopotential
Capacitive Electrodes
Common-Mode Interference
Driven-Right-Leg Circuit
Insulating Electrodes
Non-Contact Measurements
https://purl.org/becyt/ford/2.2
https://purl.org/becyt/ford/2
Descripción
Sumario:Capacitive electrodes allow to pick-up biopotentials through a dielectric layer, without using electrolytes. However, this technique is vulnerable to electric-field interference, mainly to common mode voltages produced by the 50 Hz power-line. A fully Capacitive Driven Right Leg (CDRL) circuit is proposed to reduce the patient common mode voltage vCM. The design of this circuit takes into account several factors as electrode impedance, stray coupling capacitances and amplifier transfer function response. All these parameters are addressed to ensure the circuit's stability in most biopotential acquisition scenarios. Monte Carlo analyses were performed to find the worst conditions, resulting in a maximum CDRL gain between 70 and 80 dB. The CDRL was implemented as an independent block that can be used for different applications such as ECG, EMG or EEG. Several experimental results are presented, showing good quality recordings even using SE amplifiers, an appropriate approach for multichannel acquisition systems.