This article has been accepted for inclusion in a future issue of this journal. Content is final as presented, with the exception of pagination. IEEE JOURNAL OF SOLID-STATE CIRCUITS 1 A Configurable 12–237 kS/s 12.8 mW Sparse-Approximation Engine for Mobi

Abstract—Compressive sensing (CS) is a promising technology for realizing low-power and cost-effective wireless sensor nodes (WSNs) in pervasive health systems for 24/7 health monitoring. Due to the high computational complexity (CC) of the recon-struction algorithms, software solutions cannot fulfill the energy efficiency needs for real-time processing. In this paper, we present a 12—237 kS/s 12.8 mW sparse-approximation (SA) engine chip that enables the energy-efficient data aggregation of compressively sampled physiological signals on mobile platforms. The SA engine chip integrated in 40 nm CMOS can support the simultaneous reconstruction of over 200 channels of physiological signals while consuming <1 % of a smartphone’s power budget. Such energy-efficient reconstruction enables two-to-three times energy saving at the sensor nodes in a CS-based health monitoring system as compared to traditional Nyquist-based systems, while providing timely feedback and bringing signal intelligence closer to the user. Index Terms—Application-specific integrated circuits (ASICs), biomedical signal processing, compressed sensing, digital inte-grated circuits, energy efficiency, low-power design, minimization methods, parallel architecture, real-time systems, reconfigurable architecture, signal reconstruction. I