A family of alternating current amplifiers for ultra-low frequency operation

A family of capacitively coupled alternating current (AC) amplifiers featuring ultra-low (below 1 Hz) corner frequency is presented. This is achieved by using high-gain devices which actively boost feedback resistance and thus reduce corner frequency. This procedure is often termed, though with a di...

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Detalles Bibliográficos
Autores: Martincorena Arraiza, Maite, Carlosena García, Alfonso, Cruz Blas, Carlos Aristóteles de la, Beloso Legarra, Javier, López Martín, Antonio
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Universidad Pública de Navarra
Repositorio:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/41489
Acceso en línea:https://hdl.handle.net/2454/41489
Access Level:acceso abierto
Palabra clave:AC amplifiers
Biosignal amplifiers
Bootstrapping
DC-blocking
High-pass amplifiers
Network transformation
Nullors
Descripción
Sumario:A family of capacitively coupled alternating current (AC) amplifiers featuring ultra-low (below 1 Hz) corner frequency is presented. This is achieved by using high-gain devices which actively boost feedback resistance and thus reduce corner frequency. This procedure is often termed, though with a different purpose, as 'bootstrapping'. The proposed architectures are very general and admit several possible practical implementations. To demonstrate their usefulness, the circuits are implemented with two operational amplifiers (OA), but other active devices such as operational transconductance amplifiers (OTAs) can be alternatively used. All circuits have been theoretically analyzed, extensively simulated and measured, exhibiting high-pass cutoff frequencies as low as 30 mHz.