A Solar-Cell-Assisted, 99.66% Biofuel Cell Area Reduced, Biofuel-Cell-Powered Wireless Biosensing System in 65-nm CMOS for Continuous Glucose Monitoring Contact Lenses

A 0.5-mm2 Solar Cell-Powered Biofuel Cell-Input Biosensing System With LED Driving for Stand-Alone RF-Less Continuous Glucose Monitoring Contact Lens

“…Three types of PN junctions, i.e., P-well(PW)/N+, PW/deep-N-well (DNW), and P substrate (PS)/DNW, can be used as photodiodes in the standard triple-well CMOS process. As a counterpart of solar cells [7], this work changes the wire connection to attain a higher open-circuit voltage. In order to provide more power from the constrained area, this work implemented two patterns of solar cells with different processes and pitch.…”

“…Consequently, BFC is only utilized as a sensing element due to its available sub-nW power [6]. Solar cell (SC) is a promising substitute for BFCs as localized energy harvester for LED driving on contact lenses which can provide 100s times larger power than BFCs in a unit area [7], but the unstable solar power supply is an obstacle. A 0.5 mm Extended from [8], this letter presents the first CGM contact lens by both localized energy generation and information display, with additional details on solar cell implementations, circuit diagrams, and function validation of energy harvester across varying light conditions.…”

A Solar-Cell-Assisted, 99% Biofuel Cell Area Reduced, Biofuel-Cell-Powered Wireless Biosensing System in 65nm CMOS for Continuous Glucose Monitoring Contact Lenses

“…Therefore, the biological information can be noticed according to the output power, which can be read out by RF, [1][2][3][4], or light signal [5]. These features are promising in continuous glucose monitoring (CGM) contact lens applications [3], [6], [7], since glucose BFC can harvest energy from tear glucose in human eyes that correlates with human blood glucose [8].…”

“…Furthermore, a self-controlled dual-oscillator-based supply voltage monitor [9], powered by the BFC, is used to monitor the BFC output correlated biological signals. This proposed architecture enables 99% BFC area reduction, [7], compared with the state-of-the-art BFC-based biosensing systems [1][2][3].…”

“…Finally, Section 4 concludes this brief. In addition, this brief is an extended version of the previous conference paper [7]. A block diagram of the proposed solar-cell-assisted BFCpowered wireless biosensing systems and the conceptual image for area-constrained CGM contact lenses are shown in Fig.…”