RMMIC: A 40 μW Reconfigurable Multi-modal Multi-channel Interface Circuit System for Bio-signals Monitoring

Monitoring our multi-biological signals (bio-signals) provides us with a holistic view of our physiological condition (Figure 1). With increasing demand for integrating multiple bio-signals into a single chip, it is imperative to address multiple design challenges for efficient multi-modal biosensor acquisition [1]. The bio-signals include bio-potential signals (ExG), photo-plethysmography signals (PPG), and bio-impedance signals (BioZ) that are all unique in their electric properties (voltage, current, and resistance), have a large dynamic range (4 × order magnitudes in frequency and amplitude), and have a tremendous amount of variation among channels (middle of the Figure 1). The challenge of amplifying and quantizing diverse in-band bio-signals with a single signal acquisition circuit has attracted significant attention among researchers [2-6].