A 2.18-pJ/conversion, 1656-<i>μ</i>m² Temperature Sensor With a 0.61-pJ·K² FoM and 52-pW Stand-By Power

Abstract

This letter describes a miniature, ultra low power, all-dynamic temperature sensor based on a duty-cycled resistive transducer bridge and a 9-bit asynchronous SAR ADC in 65-nm CMOS. It features a novel floating bridge technique and automatic power gating to achieve the lowest reported power consumption. It consumes 2.18 pJ per conversion and has an RMS resolution of 0.53 K, leading to an FoM of 0.61 pJ·K <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . A standby power of 52 pW allows a high power-efficiency, even at low sample rates. It occupies 36×46 μm of chip area and has a sensing range from -20 °C to 120 °C.