A MEMS Coriolis-Based Mass-Flow-to-Digital Converter for Low Flow Rate Sensing

Arthur Campos De Oliveira*, Sining Pan, Remco J. Wiegerink, Kofi A.A. Makinwa

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

3 Citations (Scopus)
3 Downloads (Pure)

Abstract

This article presents a microelectromechanical system (MEMS) Coriolis-based mass-flow-to-digital converter (Φ DC) that can be used with both liquids and gases. It consists of a micromachined Coriolis mass flow sensor and a CMOS interface circuit that drives it into oscillation and digitizes the resulting mass flow information. A phase-locked loop (PLL) drives the sensor at its resonance frequency (fD), while a low 1/f noise switched-capacitor (SC) proportional-integral (PI) controller maintains a constant drive amplitude. Mass flow through the sensor causes Coriolis-force-induced displacements, which are detected by co-integrated sense capacitors. In-phase (I) and quadrature (Q) components of these displacements are then digitized by two continuous-time delta-sigma modulators (CT- ΔΣ Ms) with finite impulse response (FIR)-DACs and passive mixers. Their outputs are used to accurately estimate and cancel sense path delay, thus improving sensor stability. To ensure constant sensitivity over a wide range of fluid densities, a background sensitivity tuning (BST) scheme adjusts the sense capacitors' bias voltage as a function of fD, which is a good proxy for fluid density. Implemented in a standard 0.18- μm CMOS technology, the interface circuit consumes 13 mW from a 1.8-V supply. The proposed MEMS Coriolis Φ DC achieves a state-of-the-art noise floor of 80 μg/h/√ Hz and a zero stability (ZS) of ±0.31 mg/h, which is at par with MEMS thermal flow sensors.

Original languageEnglish
Pages (from-to)3681-3692
Number of pages12
JournalIEEE journal of solid-state circuits
Volume57
Issue number12
DOIs
Publication statusPublished - 1 Dec 2022

Keywords

  • Capacitive interface
  • CMOS readout interface
  • Coriolis mass flow sensor
  • Delta-sigma modulator (δσM)
  • Demodulator
  • Flow rate
  • Flowmeter
  • Low noise
  • Microelectromechanical systems (MEMS)
  • Microfluidics
  • 2024 OA procedure

Fingerprint

Dive into the research topics of 'A MEMS Coriolis-Based Mass-Flow-to-Digital Converter for Low Flow Rate Sensing'. Together they form a unique fingerprint.

Cite this