This paper presents two high-resolution CMOS temperature sensors intended for the temperature compensation of MEMS/quartz frequency references. One is based on a Wien bridge RC filter, which outputs a temperature-dependent phase shift when driven by a stable frequency; the other is based on a Wheatstone bridge, which outputs a temperature-dependent current. The bridge outputs are digitized by energy-efficient continuous-time delta-sigma modulators. Two prototypes were fabricated in a standard 0.18 μm CMOS technology. Both dissipate less than 200 μW and achieve sub-mK resolution, as well as sub-0.2pJ·K2 resolution FoMs, which corresponds to state-of-the-art energy efficiency.
|Title of host publication||Hybrid ADCs, Smart Sensors for the IoT, and Sub-1V & Advanced Node Analog Circuit Design|
|Editors||Pieter Harpe, Kofi A.A. Makinwa, Andrea Baschirotto|
|Place of Publication||Cham|
|Number of pages||18|
|Publication status||Published - 2017|