MEMS gyroscope control circuit

A method, comprising:

• driving a driving mass of a microelectromechanical system (MEMS) gyroscope in a mechanical oscillation at a resonant drive frequency;
• wherein driving comprises:
• sensing the mechanical oscillation;
• and
• processing a signal dependent on the sensed mechanical oscillation in response to a system clock signal to generate a drive signal for application to cause movement of the driving mass;
• and
• generating the system clock signal independent of and asynchronous to the resonant drive frequency.

A method, comprising:

• driving a driving mass of a microelectromechanical system (MEMS) gyroscope in a mechanical oscillation at a resonant drive frequency;
• sensing a Coriolis displacement of the sensing mass;
• processing a signal dependent on the sensed Coriolis displacement in response to a system clock signal to generate an angular velocity output signal indicative of the Coriolis displacement;
• and
• generating the system clock signal independent of and asynchronous to the resonant drive frequency;
• wherein processing comprises performing an analog-to-digital conversion clocked by a first clock signal generated from the system clock signal.

A method, comprising:

• driving a driving mass of a microelectromechanical system (MEMS) gyroscope in a mechanical oscillation at a resonant drive frequency;
• sensing a Coriolis displacement of the sensing mass;
• processing a signal dependent on the sensed Coriolis displacement in response to a system clock signal to generate an angular velocity output signal indicative of the Coriolis displacement;
• and
• generating the system clock signal independent of and asynchronous to the resonant drive frequency;
• wherein processing comprises:
• generating an analog Coriolis sinusoid signal having a frequency and phase corresponding to a frequency and phase of the Coriolis displacement of the sensing mass;
• performing an analog-to-digital conversion of the analog Coriolis sinusoid signal in response to a first clock signal generated from the system clock signal to generate a digital Coriolis sinusoid signal;
• generating an in phase digital sinusoid signal in response to a frequency and phase of the mechanical oscillation of the driving mass;
• mixing the in phase digital sinusoid signal with the digital Coriolis sinusoid signal to generate a rate signal indicative of a sensed angular velocity for the angular velocity output signal;
• and
• digitally filtering the rate signal in response to a second clock signal generated from the system clock signal.

A method, comprising:

• driving a driving mass of a microelectromechanical system (MEMS) gyroscope in a mechanical oscillation at a resonant drive frequency;
• sensing a Coriolis displacement of the sensing mass;
• generating a quadrature error signal from a quadrature component of the sensed Coriolis displacement;
• processing the quadrature error signal in response to a system clock signal to generate a quadrature error compensation force for application to the sensing mass;
• and
• generating the system clock signal independent of and asynchronous to the resonant drive frequency.