Thermal Characterization of Scale-Factor and Zero-Rate Offset in Near-Navigation-Grade Nems-Based Gyroscopes
Andrea Buffoli, Marco Gadola, Marc Sansa, Patrice Rey, Philippe Robert, Giacomo Langfelder
Abstract
This work presents further advancements on miniaturized gyroscopes based on NEMS sensing, towards navigation grade applications, discussing in particular the thermal characterization of scale-factor (SF) and zero-rate-offset (ZRO). The gyroscope design, fitting in 1.3 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> only, maximizes the electromechanical transduction with resistive NEMS-gauge sensing. In terms of input-referred rate, this approach reduces both noise and drift effects originating after the conversion from rate into electrical signals. Besides reaching navigation-grade performance for noise (0.005 °/✓hr) and bias instability (0.015 °/hr), the gyroscope shows native offset drift of 275 μdps/K only (average of absolute values over 6 samples), an unrivaled result for devices of this size, package cost and consumption. After linear calibration, offsets remain within ±5 mdps (5°C-85°C range) and scale factor drifts are limited to ± 1500 ppm.