Low-Noise Operational Amplifier Design for Biomedical Instrumentation

The design of low-noise operational amplifiers (op-amps) is critical for biomedical instrumentation, where signals of extremely low amplitudes, such as electrocardiograms (ECG) and electroencephalograms (EEG), must be accurately amplified without degradation. This paper presents a comprehensive study on the design, simulation, and optimization of a low-noise opamp suitable for biomedical applications. Key noise sources are identified and minimized through design choices such as transistor sizing, biasing strategies, and topology selection. The proposed design, developed in a 180nm CMOS process, achieves a low input-referred noise of 10 nV/√Hz and operates at low power, ensuring suitability for portable medical devices. The work is validated through simulation using Cadence Virtuoso, and performance metrics are benchmarked against recent designs