This application relates to circuitry for processing sense signals generated by MEMS capacitive transducers for compensating for distortion in such sense signals. The circuitry has a signal path between an input (204) for receiving the sense signal and an output (205) for outputting an output signal based on said sense signal. Compensation circuitry (206, 207) is configured to monitor the signal at a first point along the signal path and generate a correction signal (S.sub.corr); and modify the signal at at least a second point along said signal path based on said correction signal. The correction signal is generated as a function of the value of the signal at the first point along the signal path so as to introduce compensation components into the output signal that compensate for distortion components in the sense signal. The first point in the signal path may be before or after the second point in the signal path. The monitoring may be performed in an analogue or a digital part of the signal path and in either case the modification may be applied in an analogue or a digital part of the signal path.

A microelectromechanical systems (MEMS) sensor with an integrated power management system that performs analog to digital conversion of weak signals is provided. The MEMs sensor can include a switching regulator that steps a supply voltage down to a voltage appropriate for an analog to digital converter (A/D converter). A timing circuit is provided to generate a clock frequency for the switching regulator and the A/D converter such that the clock frequencies are harmonically related. The frequency of the voltage ripples formed by the switching regulator will match the clock frequency provided to the switching regulator. When the sampling frequency of the A/D converter is harmonically related to the voltage ripple frequencies, the aliasing frequency will fall outside a range of frequencies associated with the analog signal.

An inertial measurement device for providing output sensor data according to a force or motion applied on the inertial measurement device includes a sensor unit including one or more sensor elements for detecting motion and being configured to continuously provide motion sensor data samples for each of the sensor elements. A processing unit is configured to filter data depending on or corresponding to the motion sensor data samples obtained by the sensor elements in order to provide the output sensor data. The processing unit is configured to select one or multiple filter parameter sets determined by at least one predetermined rule applied on the sensor data samples and to filter the data based on the selected filter parameter set.

Wireless piezoelectric accelerometers and systems are provided. A wireless piezoelectric accelerometer may comprise a piezoelectric sensing element configured to sense mechanical acceleration and produce an electrical charge signal in response of the sensed mechanical acceleration, a signal processing module (SPM) configured to convert the electrical charge signal into a voltage signal, and process and digitize the voltage signal, and a wireless module configured to modulate and transmit the digitized voltage signal as wireless signals. The piezoelectric sensing element, the SPM and the wireless module are packaged in a casing. The casing comprises a metallic shielding chamber configured to enclose the piezoelectric sensing element. The casing further comprises a non-metallic portion located in relative to the wireless module to allow transmission of the wireless signals. Corresponding wireless piezoelectric accelerometer systems are also provided.

According to one embodiment, a sensor includes a stage, a driver, and a detector. The stage includes a first portion and a second portion. The driver is configured to rotate the stage. A rotation axis of the stage passes through the first portion and is along a first direction. A second direction from the first portion to the second portion crosses the first direction. The second portion is configured to rotate along a circumferential direction with the rotation axis as a center when the stage rotating. The detector is provided at the second portion. The detector includes a first detection element configured to detect a first acceleration including a component along the second direction, and a second detection element configured to detect a second acceleration including a component along the first direction.

An inertial measurement device includes: an inertial sensor; a first signal processing circuit; a second signal processing circuit; a first communication unit and a second communication unit configured to communicate with an external device; and a mode selection unit configured to select a processing mode from a plurality of modes including a first processing mode and a second processing mode. The first processing mode is a mode in which the inertial measurement device is used alone and outputs a signal processed by the first signal processing circuit from the first communication unit, and the second processing mode is a mode in which the inertial measurement device is used in a state of being coupled to another inertial measurement device, a first signal processed by the first signal processing circuit and a second signal from another inertial measurement device received from the second communication unit are subjected to a calculation process by the second signal processing circuit, and a signal subjected to the calculation process is output from the first communication unit.

Apparatus and methods for equalizing microelectromechanical systems (MEMS) sensors are disclosed. In certain embodiments, measured sensor parameters of a MEMS sensor are stored in a non-volatile memory (NVM) of a sensor signal processor used to process a sensor output signal of the MEMS sensor. The measured sensor parameters are retrieved by a digital signal processor (DSP) and used for equalizing sensor data provided to the DSP by the sensor signal processor during operation. The measured sensor parameters can be determined at test, per individual part, by measurements of the MEMS sensor's characteristics, and thus equalize the MEMS sensor while accounting for manufacturing and/or processing variations.

A method for measuring the response of a MEMS accelerometer at accelerations greater than 1 G uses test electrodes to apply an acceleration to proof masses during a test procedure. The MEMS accelerometer is placed in one orientation where test electrodes apply an electromagnetic force to the proof mass, where sense electrodes then detect those movements. Afterwards, the test electrodes apply another electromagnetic force, but with the MEMS accelerometer in another orientation (e.g., opposite the first orientation). The sense signals may be converted into a transfer characteristic that may be compared to other MEMS accelerometers to determine particular characteristics of the MEMS accelerometer such as operability, best-use application, failure point, and sensitivity.

According to one embodiment, According to one embodiment, a sensor includes a first element portion, and a first circuit portion. The first element portion includes a first base, a first fixed portion, a first movable portion, first to fourth fixed electrodes. The first movable portion includes first to fourth movable electrodes. The first circuit portion includes a controller. The controller is configured to perform a first operation. The first operation includes deriving a first value corresponding to a vibration direction of the first movable portion based on a first signal obtained from the first fixed electrode and a second signal obtained from the second fixed electrode. The first operation includes synchronously detecting a first function value of the first value and a second function value of the first value.

An accelerometer system including an accelerometer comprising a proof mass assembly the proof mass assembly comprising: a plurality of dampening plates; at least two proof mass elements, wherein each proof mass element of the at least two proof mass elements is disposed between two dampening plates of the plurality of dampening plates; and a plurality of resonators, wherein at least two resonators of the plurality of resonators is coupled to each proof mass element of the at least two proof mass elements.