A Batteryless Electrochemical Sensing System IC Based on Intra-Body Power and Data Transfer Towards Miniaturized Wearable Sensor Nodes

Abstract

A batteryless electrochemical sensing system IC for miniaturized wearable sensor nodes is presented. A battery-powered hub node transmits the power and control signal required for the operation of sensor nodes through a human body. The sensor data acquired by sensor nodes are transmitted to the hub node, again through a body channel, using frequency modulation (FM). The intra-body power and data transfer leads to batteryless sensor node operation, and the direct-FM-based sensor interface using a current-controlled oscillator (26.8 and 44.9 kHz/$\mu\mathrm{A}$) simplifies sensor node hardware, which enables miniaturized wearable sensor nodes. By adding a proper multiplexing scheme among sensor nodes, the proposed system can be extended to a further advanced system consisting of distributed wearable sensor nodes.