Low-Power Vibratory Gyroscope Readout

MEMS gyroscopes are used in a wide range of consumer and automotive applications, for instance for image stabilization in cameras, and for electronic stability control and navigation in cars. This chapter focuses on techniques for reducing the power consumption of MEMS gyroscopes. After a review of the operating principles of vibratory gyroscopes, mode‐matching is introduced as a means to maximize the output signal and thus reduce power dissipation. A tuning loop is used that continuously senses the mismatch between the drive and sense modes of a gyroscope by means of two pilot tones, and electrostatically adjusts the resonance frequency to match the modes. The chapter discusses in detail the implementation of the required feedback controller and includes experimental results showing that more than 30dB improvement in the Coriolis acceleration noise floor can be obtained compared to traditional solutions dissipating the same amount of power.