Design of a CMOS FD-NIRS System With Fully Integrated Analog Front-End and Readout

Alper Kılıç, Valencia Koomson

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Keywords: Frequency domain near infrared spectroscopy, analog front-end, transimpedance amplifier, amplitude detection, phase detection, heterodyne

TL;DR: An integrated dual-channel FD-NIRS system with on-chip laser driver, analog front-end, and amplitude/phase detection with 0.02° precision, in 180 nm CMOS achieves high gain, wide bandwidth, and sub-degree phase resolution for wearable biomedical use.

Abstract: An integrated, dual-channel, Frequency Domain Near Infrared Spectroscopy system with integrated laser driver, analog front-end, phase and amplitude detection is designed in 180nm XFAB PDK. The system can accommodate both multi-distance and Dual Slope methods. The channels were designed to have 145-MHz bandwidth with 8 picofarad photodetector junction capacitance, provide $\sim$115dB gain with 56 dB dynamic range and measure the phase difference between channels with 0.02° resolution.

Track: 2. Sensors and systems for digital health, wellness, and athletics

NominateReviewer: Valencia Koomson, [e-mail]

Submission Number: 138