An inertial sensor includes a movable element having a mass that is asymmetric relative to a rotational axis and anchors attached to the substrate. First and second spring systems are spaced apart from the surface of the substrate. Each of the first and second spring systems includes a pair of beams, a center flexure interposed between the beams, and a pair of end flexures. One of the end flexures is interconnected between one of the beams and one of the anchors and the other end flexure is interconnected between one of the beams and the movable element. The beams are resistant to deformation relative to the center flexure and the end flexures. The first and second spring systems facilitate rotational motion of the movable element about the rotational axis and the spring systems facilitate translational motion of the movable element substantially parallel to the surface of the substrate.

An inventive accelerometer includes a proof mass and a pair of vibrating sensors. An excitation-and-detection circuit drives one sensor at resonant frequencies f.sub.1 and F.sub.1, with f.sub.1?F.sub.1; a second excitation-and-detection circuit drives the other sensor at resonant frequencies f.sub.2 and F.sub.2, with f.sub.2?F.sub.2. The vibrational modes driven at the frequencies f.sub.1 and f.sub.2 are the same for each sensor; the vibrational modes driven at the frequencies F.sub.1 and F.sub.2 are the same for each sensor. Compressive or tensile loads oppositely applied by the proof mass to the vibrating sensors cause a difference frequency ?F=F.sub.1?F.sub.2 to vary monotonically with acceleration of the apparatus along a sensing axis, from which a measurement of acceleration can be generated.

An inventive accelerometer includes a proof mass, vibrating sensors, and an excitation-and-detection circuit. The vibrating sensors are substantially identical, and each exhibits corresponding fundamental and higher-order vibrational modes characterized by corresponding fundamental and higher-order resonant mode frequencies. The excitation-and-detection circuit drives each corresponding vibrating sensor at one of its resonant mode frequencies f.sub.1 or f.sub.2; the vibrational modes driven at the frequencies f.sub.1 and f.sub.2 are the same for each sensor. Compressive or tensile loads oppositely applied by the proof mass to the vibrating sensors cause a difference frequency ?f=f.sub.1?f.sub.2 to vary monotonically with acceleration of the apparatus along the sensing axis. The excitation-and-detection circuit includes at least one low-pass filter with a low-pass cut-off frequency f.sub.LP that is less than ?f.

The present disclosure related to a micro-electromechanical system (MEMS) device and a method of forming the same. The MEMS device includes a substrate, a cavity, an interconnection structure and a proof mass. The substrate includes a first surface and a second surface opposite to the first surface. The cavity is disposed in the substrate to extend between the first surface and the second surface. The interconnection structure is disposed on the first surface of the substrate, over the cavity. The proof mass is disposed on the interconnection structure, wherein the proof mass is partially suspended over the interconnection structure.

An inventive accelerometer includes a proof mass and a pair of vibrating sensors. Excitation-and-detection circuits drive vibrational modes of one sensor at resonant frequencies f.sub.1, F.sub.1, and F.sub.1, and drive those same vibrational modes of the other sensor at resonant frequencies f.sub.2, F.sub.2, and F.sub.2. Compressive or tensile loads oppositely applied by the proof mass to the vibrating sensors cause difference frequencies ?f=f.sub.1?f.sub.2, ?F=F.sub.1?F.sub.2, and ?F=F.sub.1?F.sub.2 to vary monotonically with acceleration of the apparatus along a sensing axis. A measurement of acceleration can be generated based at least in part on a linear or nonlinear function of one or more or all of f.sub.1, f.sub.2, F.sub.1, F.sub.2, F.sub.1, or F.sub.2, and can be generated using a trained neural network.

Linear accelerometer comprising a fixed part, a rotationally moving part in the plane of the accelerometer around an axis of rotation orthogonal to the plane of the accelerometer, the moving part comprising a centre of gravity distinct from the point of intersection of the axis of rotation and the plane of the accelerometer, means forming pivot link between the moving part and the fixed part, means for detecting the displacement of the moving part with respect to the fixed part, means for viscous damping the displacement of the moving part in said plane, said viscous damping means comprising interdigitated combs, at least one first comb on the moving part and at least one second comb on the fixed part (2), the first comb and the second comb being interdigitated.

A microelectromechanical system (MEMS) accelerometer is described. The MEMS accelerometer is arranged to limit distortions in the detection signal caused by displacement of the anchor(s) connecting the MEMS accelerometer to the underlying substrate. The MEMS accelerometer may include masses arranged to move in opposite directions in response to an acceleration of the MEMS accelerometer, and to move in the same direction in response to displacement of the anchor(s). The masses may, for example, be hingedly coupled to a beam in a teeter-totter configuration. Motion of the masses in response to acceleration and anchor displacement may be detected using capacitive sensors.

A micromechanical structure for an acceleration sensor, including a seismic mass that is constituted definedly asymmetrically with reference to the rotational Z axis of the structure of the acceleration sensor, spring elements that are fastened on the seismic mass and on at least one fastening element, a rotational motion of the seismic mass being generatable by way of the spring elements substantially only upon an acceleration in a defined sensing direction within a plane constituted substantially orthogonally to the rotational Z axis.

Techniques for an integrated circuit including an accelerometer are provided. In an example, an apparatus can include a unitary silicon substrate including a first portion and a second portion, wherein the first portion is thinner than the second portion, at least a portion of a sensor circuit configured to measure a deflection of the second portion with respect to the first portion, wherein the first portion is configured to anchor the accelerometer to a second device, and wherein the second portion is configured to deflect relative to the first portion in response to acceleration of the apparatus.

The MEMS sensor of the invention has movable and fixed components for measuring acceleration in a rotational mode in a direction in-plane perpendicular to spring axis. The components include an element frame, a substrate, a proof-mass a spring connected to the proof-mass and to the substrate, and comb electrodes. The MEMS sensor is mainly characterized by an arrangement of the components causing an inherent sensitivity for measuring accelerations in a range covering longitudinal and transversal accelerations. One or more of the components are tilted compared to the element frame. The semiconductor package of the invention comprises at least one MEMS sensor.