Use of electronic attenuator for MEMS oscillator overdrive protection

摘要

An apparatus includes a microelectromechanical system (MEMS) device configured as part of an oscillator. The MEMS device includes a mass suspended from a substrate of the MEMS, a first electrode configured to provide a first signal based on a displacement of the mass, and a second electrode configured to receive a second signal based on the first signal. The apparatus includes an amplifier coupled to the first electrode and a first node. The amplifier is configured to generate an output signal, the output signal being based on the first signal and a first gain. The apparatus includes an attenuator configured to attenuate the output signal based on a second gain and provide as the second signal an attenuated version of the output signal.

主权项

1. An apparatus comprising:
a microelectromechanical system (MEMS) device configured as part of an oscillator comprising:
a mass suspended from a substrate of the MEMS;a first electrode configured to provide a first signal based on a displacement of the mass; anda second electrode configured to receive a second signal based on the first signal; an amplifier coupled to the first electrode and a first node, the amplifier configured to generate an output signal, the output signal being based on the first signal and a first gain; an attenuator configured to attenuate the output signal based on a second gain and provide as the second signal an attenuated version of the output signal; and an automatic amplitude control module configured to generate a feedback signal based on a reference signal level and the second signal, wherein the amplifier adjusts the first gain based on the feedback signal.