Systems and methods to stabilize high-Q MEMS sensors
View Patent ↗Various embodiments of the invention allow to reduce unwanted high-Q oscillations in capacitive MEMS sensors. In certain embodiments, stabilization of high-Q MEMS sensors is accomplished through a dedicated ultra-low power circuit that provides a bias voltage to one or more sensor electrodes during an OFF-phase. The bias voltage forces a balance condition that eliminates perturbations and enables smooth transitions that, ultimately, result in shorter sensor settling times.
1. A method to stabilize a high-Q MEMS sensor, the method comprising:
receiving a sensor signal from a sensor:
applying a bias voltage to the sensor:
amplifying the biased sensor voltage using a front-end amplifier circuit:
outputting the amplified and biased sensor signal from a front-end readout circuit:
de-energizing the front-end amplifier circuit: and
applying a bias control voltage to the sensor, wherein the bias control voltage causes an average electrostatic force applied to at least two sensor electrodes to be equal in a first phase and a second phase.
2. The method according to claim 1 , wherein the sensor signal is generated in response to receiving a pulsating input voltage.
3. The method according to claim 1 , wherein generating the sensor signal occurs in response to receiving data related to a position of a proof-mass.
4. The method according to claim 1 , wherein the bias control voltage to the sensor is applies to a differential sensor output signal.
5. The method according to claim 1 , wherein the bias control voltage is applied to the sensor via a voltage source.