A Quadrature Phase-Locked Loop Based Digital Closed-Loop System for MEMS Resonant Sensors

• DOI: 10.1109/sensors56945.2023.10325265
• Publication Date: 2023-11-28T19:02:53Z
• Authors: Mengyang Zhou; Jiahui Yao; Yulan Lu; Bo Xie; Junbo Wang; Deyong Chen; Jian Chen; Xiaoye Huo; Nan Lil
• Keywords: Quadrature (astronomy); Linearity; Allan variance; Digital Control

This paper reports a novel digital closed-loop system for micro-electromechanical systems (MEMS) resonant sensors. The achieves frequency tracking through quadrature phase-locked loop (QPLL) and creatively incorporates configurable phase-shifting module. Additionally, an innovative amplitude control module, utilizing feedback adjustment, enables stable vibration of the resonator mitigates negative effects resulting from variations in quality factor at different temperatures. has been implemented on field-programmable gate array (FPGA) development board validated MEMS temperature sensor, which exhibits significant changes across range -40 to 80°C. design module reduces sensitivity errors by approximately 14-fold improves linearity nearly order magnitude. bias instability evaluated Allan variance is as low <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$3.4\times 10^{-4}{}^{\circ}\mathrm{C}$</tex> .