Design and Comparative Analysis of a Low-Power Subthreshold Folded Cascode Variable Gain Amplifier in 90 nm and 45 nm CMOS Technology

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Abstract

Variable gain amplifiers have been of great research interest in recent years. With increasing applications in biomedical systems, it becomes essential to design low-power models of the same. This paper proposes an ultra-low power variable gain amplifier using a Gilbert Cell and provides a comparative analysis across 90 nm and 45 nm CMOS technologies. The proposed design operates at a supply voltage of 0.5 V and achieves an adjustable gain range with a maximum gain of 31 dB. This amplifier operates in the subthreshold region, enabling a power dissipation as low as 10 nW while maintaining a significantly large 3 dB bandwidth.

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Keywords

Variable gain amplifier; Subthreshold; Folded Cascode; Gilbert Cell; Low Power