A 0.9-2.6pW 0.1-0.25V 22nm 2-bit Supply-to-Digital Converter Using Always-Activated Supply-Controlled Oscillator and Supply-Dependent-Activation Buffers for Bio-Fuel-Cell-Powered-and-Sensed Time-Stamped Bio-Recording

This paper presents a low-power supply-to-digital converter for bio-recording system where bio fuel cell provides both power and sensing data. It is achieved by supply-controlled oscillator, supply-dependent activation buffers (SDAB), and encoders. A 22-nm prototype chip exhibits its feasibility with a power of 0.9-2.6 pW under 0.1-0.25 V. Keywords: IoT, supply-dependent-activation buffer, CGM