A 150nW CMOS novel temperature sensor for remote patient monitoring based on an auto-resonant active inductor architecture

An ultra low power temperature sensor suitable for human body range monitoring has been implemented using a standard 2P4M 0.35 μm CMOS process. This sensor is based on a novel Time-to-Digital Converter (TDC) architecture, which makes use of an auto-resonant cascode gyrator-C active inductor. The fabricated sensor has an active area less than 200 μm × 300 μm. It has a 0.03 °C resolution and a ±0.15 °C inaccuracy and allows high data rates with a conversion time lower than 200 μs and a power consumption less than 150 nW @ 10 samples/s.