A 1.2V 10µW NPN-based temperature sensor in 65nm CMOS with an inaccuracy of ±0.2°C (3s) from −70°C to 125°C

Abstract

This paper describes a temperature sensor realized in a 65nm CMOS process with a batch-calibrated inaccuracy of ±0.5°C (3s) and a trimmed inaccuracy of ±0.2°C (3s) from −70°C to 125°C. This represents a 10-fold improvement in accuracy compared to other deep-submicron temperature sensors [1,2], and is comparable with that of state-of-the-art sensors implemented in larger-feature-size processes [3,4]. The sensor draws 8.3µA from a 1.2V supply and occupies an area of 0.1mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , which is 45 times less than that of sensors with comparable accuracy [3,4]. These advances are enabled by the use of NPN transistors as sensing elements, the use of dynamic techniques i.e. correlated double sampling (CDS) and dynamic element matching (DEM), and a single room-temperature trim.