The teaching objective of this case is to illustrate the effective use of circuit analysis and simulation for developing a MEMS gyroscope drive circuit with feedback control. The case will give students the opportunity to evaluate commercially available components (AGC, PLL and VGC).
Frequency Modulated Gyroscope Driving Circuit Design
Case revision date:
The University of Waterloo (UW) has consistently been ranked as one of the top ten universities in Canada. UW operates and manages 41 research centres and institutes, including the Waterloo Institute for Nanotechnology (WIN) and the Institute for Quantum Computing (IQC). A number of research groups exist within WIN including the Nano and Micro Systems Lab (NMSL). The NMSL group conducts research in state-of-the-art micro- and nano-sensing and actuation technologies. This research addresses issues in global healthcare and energy as well as being of environmental importance and contributing to fundamental sciences. One of the NMSL’s recent research aims was to develop a novel cantilever beam Micro-electromechanical Systems (MEMS) gyroscope with frequency modulated (FM) readout, Figure 1. In order to demonstrate the concept, a prototype MEMS gyroscope was designed and fabricated using the Teledyne Dalsa MEMS Integrated Design for Inertial Sensors (MIDIS™) Process. The gyroscopes undergo coupled flexural vibrations in two orthogonal directions when subjected to base rotation around the beam’s longitudinal axis.
The gyroscope detects angular rotations as the difference between the natural frequencies of two closely spaced drive and sense modes rather than the magnitude of displacement in the sense direction.
Noise; Sideband full carrier; RMS detector; Filters and Buffers: RLC circuit
Problem Analysis; Design; Use of Engineering Tools; Individual and Teamwork
Module 01 - Case Study
Module 02 - System Block Diagram & Conceptual Design
Module 03 - Resonant Drive Circuits and Component Selection
Module 04 - Automatic Gain Control (AGC) Circuit Design
Module 05 - Amplitude Stabilization
Module TN - Teaching Note