Patent classifications
G01C19/5762
Trim circuit and method of oscillator drive circuit phase calibration
An oscillator drive circuit and a trim circuit are implemented inside an integrated circuit of a sensor. The drive circuit provides an oscillating drive signal at a resonant frequency to drive a movable mass of the sensor. The drive circuit includes a phase shift circuit having an input for receiving a first signal indicative of an oscillation of the movable mass and having an output. The phase shift circuit adds a phase shift component to the first signal and produces a second signal shifted in phase by the phase shift component. The trim circuit includes a first comparator for receiving the first signal, a second comparator for receiving the second signal, and a processing element. The processing element determines a phase lag between the first and second signals and produces trim code for use by the phase shift circuit, the trim code being configured to adjust the phase shift component.
Trim circuit and method of oscillator drive circuit phase calibration
An oscillator drive circuit and a trim circuit are implemented inside an integrated circuit of a sensor. The drive circuit provides an oscillating drive signal at a resonant frequency to drive a movable mass of the sensor. The drive circuit includes a phase shift circuit having an input for receiving a first signal indicative of an oscillation of the movable mass and having an output. The phase shift circuit adds a phase shift component to the first signal and produces a second signal shifted in phase by the phase shift component. The trim circuit includes a first comparator for receiving the first signal, a second comparator for receiving the second signal, and a processing element. The processing element determines a phase lag between the first and second signals and produces trim code for use by the phase shift circuit, the trim code being configured to adjust the phase shift component.
MEMS-sensor
A sensor which measures parameters such as acceleration, rotation and magnetic field comprises a substrate defining a plane and at least one sensing plate suspended above the substrate for movement in a sensing direction orthogonal to the substrate plane. A detection arm suspended above the substrate is rotational about an axis parallel to the substrate plane. An out-of-plane coupling structure couples the sensing plate to the detection arm for generating rotational movement of the detection arm, which is detected by a rotation detection structure. A pivot element arranged at a distance from the coupling structure facilitates tilting movement of the sensing plate.
MEMS-sensor
A sensor which measures parameters such as acceleration, rotation and magnetic field comprises a substrate defining a plane and at least one sensing plate suspended above the substrate for movement in a sensing direction orthogonal to the substrate plane. A detection arm suspended above the substrate is rotational about an axis parallel to the substrate plane. An out-of-plane coupling structure couples the sensing plate to the detection arm for generating rotational movement of the detection arm, which is detected by a rotation detection structure. A pivot element arranged at a distance from the coupling structure facilitates tilting movement of the sensing plate.
MEMS structure
A MEMS structure includes a planar substrate, a support body coupled to the planar substrate, a fixed electrode coupled to the planar substrate and a moveable portion. The movable portion is spaced from and faces the fixed electrode. The movable electrode includes a movable weight and an intermediate frame surrounding an outer edge of the movable weight. A plurality of elastic supports connect the movable weight to the intermediate frame. The elastic supports are elastically deformable in a first direction extending parallel to the plane of the substrate such that the movable weight can move in the first direction. At least one torsion bar pivotally connects one end of the intermediate frame to the support body so as to allow the intermediate frame, and with it the movable weight, to pivot around an axis which extends parallel to the plane of the substrate and perpendicular to the first direction.
MEMS structure
A MEMS structure includes a planar substrate, a support body coupled to the planar substrate, a fixed electrode coupled to the planar substrate and a moveable portion. The movable portion is spaced from and faces the fixed electrode. The movable electrode includes a movable weight and an intermediate frame surrounding an outer edge of the movable weight. A plurality of elastic supports connect the movable weight to the intermediate frame. The elastic supports are elastically deformable in a first direction extending parallel to the plane of the substrate such that the movable weight can move in the first direction. At least one torsion bar pivotally connects one end of the intermediate frame to the support body so as to allow the intermediate frame, and with it the movable weight, to pivot around an axis which extends parallel to the plane of the substrate and perpendicular to the first direction.
GYROSCOPE WITH AUXILIARY SELF-TEST
A gyroscope includes drive electrodes that drive a drive mass at a drive frequency. A sense mass is responsive to a Coriolis force caused by rotation of the gyroscope and oscillates based on the drive frequency. Electrodes adjacent to the sense mass drive the sense mass at test frequencies. The response to the driving at the test frequencies is measured and a gyroscope failure is identified based on this response.
CONTROLLER AND METHOD FOR MINIMIZING SCALE FACTOR ERRORS OF A ROTATION RATE SENSOR
The invention relates to a controller (200) for controlling a rotation rate sensor, having a first control circuit (202) and a second control circuit (204). The first control circuit has a first control unit (210) for controlling an oscillation of the rotation rate sensor along a first direction, a first digital-to-analog converter (240) for converting a first digital control signal (215) output by the first control unit (210) into a first analog signal (245) with which the oscillation of the rotation rate sensor along the first direction is controlled, and a first analog-to-digital converter (250) for converting a first analog measurement signal (235) which describes the oscillation of the rotation rate sensor along the first direction into a first digital read-out signal (255) which is supplied to the first control unit (210). The second control circuit (204) has a second control unit (220) for controlling an oscillation of the rotation rate sensor along a second direction which is different from the first direction and a second digital-to-analog converter (270) for converting a second digital control signal (225) output by the second control unit into a second analog signal (275) with which the oscillation of the rotation rate sensor along the second direction is controlled.
CONTROLLER AND METHOD FOR MINIMIZING SCALE FACTOR ERRORS OF A ROTATION RATE SENSOR
The invention relates to a controller (200) for controlling a rotation rate sensor, having a first control circuit (202) and a second control circuit (204). The first control circuit has a first control unit (210) for controlling an oscillation of the rotation rate sensor along a first direction, a first digital-to-analog converter (240) for converting a first digital control signal (215) output by the first control unit (210) into a first analog signal (245) with which the oscillation of the rotation rate sensor along the first direction is controlled, and a first analog-to-digital converter (250) for converting a first analog measurement signal (235) which describes the oscillation of the rotation rate sensor along the first direction into a first digital read-out signal (255) which is supplied to the first control unit (210). The second control circuit (204) has a second control unit (220) for controlling an oscillation of the rotation rate sensor along a second direction which is different from the first direction and a second digital-to-analog converter (270) for converting a second digital control signal (225) output by the second control unit into a second analog signal (275) with which the oscillation of the rotation rate sensor along the second direction is controlled.
Drive and sense balanced, semi-coupled 3-axis gyroscope
A dynamically balanced 3-axis gyroscope architecture is provided. Various embodiments described herein can facilitate providing linear and angular momentum balanced 3-axis gyroscope architectures for better offset stability, vibration rejection, and lower part-to-part coupling.