An Energy-Autonomous Bio-Sensing System Using a Biofuel Cell and 0.19V 53μW 65nm-CMOS Integrated Supply-Sensing Sensor with a Supply-Insensitive Temperature Sensor and Inductive-Coupling Transmitter

This paper presents an energy-autonomous biosensing system with the capability of proximity communication. The proposed biosensor includes a biofuel cell as a power source and sensing frontend associated with the integrated supply-sensing sensor. The sensor consists of a digital-based gate leakage timer, supply-insensitive time-domain temperature sensor, and current-driven inductive-coupling transmitter and achieves low-voltage operation. The timer converts the output supply-voltage from a biofuel cell to period output. The supply-insensitive temperature sensor provides PWM output without dependency of the supply voltage. The following inductive-coupling transmitter enables proximity communication. A test chip using 65-nm CMOS technology was operated with a supply of 0.19 V and consumed 53 mu W to successfully demonstrate proximity communication with an asynchronous receiver. The measurement results show the possibility of energy-autonomous operation using biofuel cells.