34.5 Human-Body-Coupled Power-Delivery and Ambient-Energy-Harvesting ICs for a Full-Body-Area Power Sustainability

As the number of body area electronics increases, the power source is becoming a major bottleneck. Using a battery for each node is bulky and inconvenient due to the need of frequent battery replacement/recharging. Conventional harvesting methods are largely placement confined and thus unable to sustain multiple nodes of heterogeneous placements simultaneously [1], [2]. For simultaneous power delivery to multiple nodes on body, [3] utilizes the near-field inductive link for power delivery to sensor nodes placed on the eTextiles shirt and thus exhibits placement constraints, whereas the far-field RF transfer based [4] suffers from antenna pattern distortion and body shadowing effect (RF energy blocked by human body), leaving sensor nodes under such effect practically uncovered due to the 20~40 dB more channel degradation [5]. Such placement-induced nonidealities, along with distance/environment induced impedance variations and voltage/power degradations, challenges the powering system design for wider body coverage. This paper presents the full-body coverage “body-coupled power delivery” and the placement-independent “body-coupled ambient energy harvesting” ICs, achieved by the Bulk Adaptation Rectifier (BAR) and the Detuned Impedance Booster (DIB), with the power sustainability supported by the Dual Mode Buck-Boost Converter (DM-BBC).