Portable biomedical devices such as ECG, EEG, and wearable health monitors require analog
front-end circuits that operate at extremely low power while maintaining sufficient gain,
bandwidth, and noise performance. Among these circuits, the operational amplifier plays a
critical role in signal amplification and conditioning. This paper presents the design and
analysis of a low-power CMOS operational amplifier optimized for portable biomedical
applications. The proposed amplifier employs a two-stage architecture using power-efficient
biasing techniques to achieve low power consumption under low supply voltage operation.
Designed using 180 nm CMOS technology, the amplifier operates at a supply voltage of 1.8
V and consumes minimal power while providing high open-loop gain and adequate phase
margin. Simulation results demonstrate that the proposed design meets the requirements of
low-power biomedical signal processing applications.

CMOS operational amplifier, low power design, biomedical electronics, analog
integrated circuits, portable medical devices

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