Martincorena Arraiza, MaiteCruz Blas, Carlos Aristóteles de laCarlosena García, AlfonsoLópez Martín, Antonio2022-08-042022-08-042022Martincorena-Arraiza, M.; De-La-Cruz-Blas, C. A.; Carlosena, A.; Lopez-Martin, A. (2022). AC coupled amplifier with a resistance multiplier technique for ultra-low frequency operation. AEU - International Journal of Electronics and Communications. 149.1434-841110.1016/j.aeue.2022.154176https://academica-e.unavarra.es/handle/2454/43701This paper proposes a novel, tunable AC coupled capacitive feedback amplifier, exhibiting an ultra-low high pass corner frequency. This is accomplished by actively boosting the output resistive value of a MOS transistor in weak inversion. The circuit is based on a more general architecture, recently proposed by the authors, and is analyzed in terms of its capability to achieve ultra-low frequency operation, its DC performance, and noise. The proposed technique is demonstrated via measurement results from a fabricated test chip prototype using a standard 0.18 µm CMOS technology. The proposed amplifier provides a tunable high pass corner frequency from 20 mHz to 475 mHz, consuming 4.71 μW and a total area of 0.069 mm2.application/pdfeng© 2022 The Authors. This is an open access article under the CC BY-NC-ND licenseAC amplifierAnalog integrated circuitsBootstrappingLow-power circuit designSubthreshold circuit designWeak inversioninfo:eu-repo/semantics/article2022-08-04info:eu-repo/semantics/openAccess