Abstract: In an inertial sensor having a resonator and an accelerometer, acceleration signals are induced by resonating at least one shuttle of the resonator in a device plane at a shuttle resonance mode frequency and modulating the motion of the at least one resonator shuttle to induce accelerometer signals from the accelerometer. The motion may be modulated in the device plane or out of the device plane. A shuttle resonance mode and an accelerometer resonance mode may me matched based on the induced accelerometer signals, for example, by providing a feedback signal to the inertial sensor in response to such induced accelerometer signals to substantially nullify the induced accelerometer signals.

Abstract: Detecting and/or mitigating the presence of particle contaminants in a MEMS device involves converting benign areas in which particles might become trapped undetectably by electric fields during test to field-free regions by extending otherwise non-functional conductive shield and gate layers and placing the same electrical potential on the conductive shield and gate layers. Particle contaminants can then be moved into detection locations remote from the potential trap areas and having particle detection structures by providing some mechanical disturbance.

Abstract: In comb drive vibratory gyroscopes, drive-induced Coriolis accelerometer offset is effectively canceled by demodulating the output during equal times of in-phase and anti-phase drive of the shuttle with respect to the velocity signal used for angular rate demodulation. This reduces or eliminates the corresponding thermal and die-stress effects otherwise needing calibration.

Abstract: An inertial sensor includes driving piezoelectric transducers for enabling an oscillation of a resonator, sensing piezoelectric transducers for enabling a detection of a movement of the inertial sensor, and piezoelectric compensating elements substantially equidistantly among the driving and the sensing piezoelectric transducers, wherein the compensating elements and the resonator form corresponding capacitors having capacitive gaps, and wherein, during the oscillation of the resonator, changes in electrostatic charges stored in the capacitors are measured with the compensating elements and are modified so as to modify the oscillation of the resonator.

Abstract: An inertial sensor includes driving piezoelectric transducers for enabling an oscillation of a resonator, sensing piezoelectric transducers for enabling a detection of a movement of the inertial sensor, and piezoelectric compensating elements substantially equidistantly among the driving and the sensing piezoelectric transducers, wherein the compensating elements and the resonator form corresponding capacitors having capacitive gaps, and wherein, during the oscillation of the resonator, changes in electrostatic charges stored in the capacitors are measured with the compensating elements and are modified so as to modify the oscillation of the resonator.

Abstract: Detecting and/or mitigating the presence of particle contaminants in a MEMS device involves including MEMS structures that in normal operation are robust against the presence of particles but which can be made sensitive to that presence during a test mode prior to use, e.g.

Abstract: Inertial sensors with reduced sensitivity to quadrature errors and micromachining inaccuracies include a gyroscope incorporating two specially-configured single-axis gyroscopes for sensing rotations about two orthogonal axes (the axes of sensitivity) in the device plane, where each single-axis gyroscope includes a resonator having two rotationally-dithered shuttles interconnected by a fork and each shuttle is configured to tilt out-of-plane along a tilt axis perpendicular to the axis of sensitivity and includes corresponding Coriolis sensing electrodes positioned along an axis perpendicular to the tilt axis (i.e., parallel to the axis of sensitivity). The two single-axis gyroscopes may be interconnected, e.g., by one or more in-phase or anti-phase couplings interconnecting the forks and/or the shuttles.

Abstract: In an inertial sensor having a resonator and an accelerometer, acceleration signals are induced by resonating at least one shuttle of the resonator in a device plane at a shuttle resonance mode frequency and modulating the motion of the at least one resonator shuttle to induce accelerometer signals from the accelerometer. The motion may be modulated in the device plane or out of the device plane. A shuttle resonance mode and an accelerometer resonance mode may me matched based on the induced accelerometer signals, for example, by providing a feedback signal to the inertial sensor in response to such induced accelerometer signals to substantially nullify the induced accelerometer signals.

Abstract: Bulk acoustic wave (BAW) gyroscopes purposefully operate using non-degenerate modes, i.e., resonant frequencies of drive and sense modes are controlled so they are not identical. The resonant frequencies differ by a small controlled amount (?f). The difference (?f) is selected such that the loss of sensitivity, as a result of using non-degenerate modes, is modest. Non-degenerate operation can yield better bandwidth and improves signal-to-noise ratio (SNR) over comparable degenerate mode operation. Increasing Q of a BAW resonator facilitates trading bandwidth for increased SNR, thereby providing a combination of bandwidth and SNR that is better than that achievable from degenerate mode devices. In addition, a split electrode configuration facilitates minimizing quadrature errors in BAW resonators.

Abstract: One or more electrodes that interact with a movable mass in a MEMS device are anchored or otherwise supported from both the top and bottom and optionally also from one or more of the lateral sides other than the transduction side (i.e., the side of the electrode facing the mass) in order to severely restrict movement of the electrodes such as from interaction with the mass and/or external forces.

Abstract: A mode matching servo for an inertial sensor having a resonator and an accelerometer provides a test signal at a frequency higher than a predetermined inertial sensor response frequency and lower than an accelerometer resonance mode frequency so as to induce acceleration signals from the accelerometer substantially at the test signal frequency when the modes are not matched. A feedback signal is provided in response to such induced signals to substantially nullify the signals.

Abstract: In a micromachined devices having a movable shuttle driven in oscillation, measuring the electrical charge accumulated on opposing drive capacitors to determine the displacement of the movable shuttle. Alternately, in such a micromachined device, measuring the electrical charge accumulated on a drive capacitor and comparing the measured electrical charge to a nominal electrical charge to determine the displacement of the movable shuttle.

Abstract: The transduction scale factor for a MEMS gyroscope is calibrated without moving the MEMS device based on measurements of the resonator resonance frequency and the accelerometer resonance frequency as well as a distance value that may be a fixed distance value or a measured distance value. The measured distance value may be obtained by measuring the quality factor of the resonator or accelerometer and deriving the measured distance value from the quality factor measurement.

Abstract: An analog-to-digital converter includes a delta circuit, a sigma circuit, and a quantizer circuit and further includes a feedback circuit that modulates a reference voltage provided to the quantizer circuit based on the quantizer circuit output. Modulation of the quantizer reference voltage dithers the quantizer circuit to effectively reduce or avoid lock bands. The analog-to-digital converter may be used in combination with a microelectromechanical (MEMS) device such as a gyroscope, an accelerometer, or a pressure sensor.

Abstract: Detecting and/or mitigating the presence of particle contaminants in a MEMS device involves including MEMS structures that in normal operation are robust against the presence of particles but which can be made sensitive to that presence during a test mode prior to use, e.g.

Abstract: Error sources relating to the drive signal applied to the resonator of an inertial sensor, such as in-phase offset errors relating to the drive signal and/or electronic pass-through of the drive signal to accelerometer sense electronics, are detected by modulating the drive signal and sensing accelerometer signals that are induced by the modulated drive signal. Error sources related to aerodynamics of an inertial sensor resonator are detected by modulating the distance between the resonator and the underlying substrate and sensing accelerometer signals that are induced by such modulation. Compensating signals may be provided to substantially cancel errors caused by such error sources.

Abstract: Inertial sensors with reduced sensitivity to quadrature errors and micromachining inaccuracies include a gyroscope incorporating two specially-configured single-axis gyroscopes for sensing rotations about two orthogonal axes (the axes of sensitivity) in the device plane, where each single-axis gyroscope includes a resonator having two rotationally-dithered shuttles interconnected by a fork and each shuttle is configured to tilt out-of-plane along a tilt axis perpendicular to the axis of sensitivity and includes corresponding Coriolis sensing electrodes positioned along an axis perpendicular to the tilt axis (i.e., parallel to the axis of sensitivity). The two single-axis gyroscopes may be interconnected, e.g., by one or more in-phase or anti-phase couplings interconnecting the forks and/or the shuttles.

Abstract: A mode matching servo for an inertial sensor having a resonator and an accelerometer provides a test signal at a frequency higher than a predetermined inertial sensor response frequency and lower than an accelerometer resonance mode frequency so as to induce acceleration signals from the accelerometer substantially at the test signal frequency when the modes are not matched. A feedback signal is provided in response to such induced signals to substantially nullify the signals.

Abstract: A sensor element is capped by bonding or otherwise forming a cap on a sensor element. The sensor may be hermetically sealed by using a hermetic cap and hermetic bonding material or by applying a hermetic coating. The sensor may be filled with a gas at an elevated pressure. The sensor may alternatively or additionally be filled with a special gas, such as a gas having a density-to-viscosity ratio above approximately 0.2.

Abstract: An analog-to-digital converter includes a delta circuit, a sigma circuit, and a quantizer circuit and further includes a feedback circuit that modulates a reference voltage provided to the quantizer circuit based on the quantizer circuit output. Modulation of the quantizer reference voltage dithers the quantizer circuit to effectively reduce or avoid lock bands. The analog-to-digital converter may be used in combination with a microelectromechanical (MEMS) device such as a gyroscope, an accelerometer, or a pressure sensor.