An energy-autonomous, disposable, big-data-based supply-sensing biosensor using bio fuel cell and 0.23-V 0.25-?m Zero-Vth all-digital CMOS supply-controlled ring oscillator with inductive transmitter

This study demonstrates an energy-autonomous disposable supply-sensing biosensor platform for big-data-based healthcare application for the first time. The proposed supply-sensing biosensor platform is based on bio fuel cells and a 0.23-V 0.25-μm zero-V_th all-digital CMOS supply-controlled ring oscillator with a current-driven pulse-interval-modulated inductive-coupling transmitter. The all-digital and current-driven architecture using zero-V_th transistors enables low-voltage operation and small footprint even in the cost-competitive legacy CMOS, which enables converterless energy-autonomous operation using bio fuel cell for disposable healthcare application. To verify its effectiveness, a test chip was fabricated using 0.25-μm CMOS technology. The measured results successfully demonstrated operation under a 0.23-V supply, which is the lowest supply voltage among reported proximity transmitters. In addition, an energy-autonomous biosensing operation using organic bio fuel cells for transdermal patch was successfully demonstrated.