Abstract: Aspects of the present application allow for measurement of a calibrated resistance for a resistive film in a sensing element, such that effects from contact resistance and background resistance drifts due to factors such as temperature, strain or aging can be reduced or eliminated. In some embodiments, by taking a plurality of two-terminal resistance measurements between various pairs of electrodes on a resistive film, a contact-resistance-independent resistance of a reference portion of the resistive film can be determined. Further, a contact-resistance-independent resistance of a sensing portion of the resistive film can be determined based on a plurality of two-terminal resistance measurements between pairs of electrodes. The resistance of the reference portion can be removed from the measured resistance of the sensing portion, such that variations in the reference portion resistance that are not caused by a sensed environmental condition may be compensated.

Abstract: Embodiments of the present disclosure relate to cellular technology applications of beamforming performed in the digital domain. In one aspect, an RF system for performing digital beamforming on a per-carrier basis is disclosed, where different phase and/or amplitude adjustments are applied to signals of different frequency ranges (i.e., to different carrier signals). In another aspect, an RF system for performing digital beamforming on a per-antenna basis is disclosed, where different phase and/or amplitude adjustments are applied to signals transmitted from or received by different antennas. In some embodiments, an RF system may be configured to implement both digital beamforming on a per-carrier basis and digital beamforming on a per-antenna basis. The RF systems disclosed herein allow implementing programmable beamforming in the digital domain in a manner that is significantly less complex than conventional implementations.

Abstract: Apparatus and methods for tunable filtering are provided. In certain embodiments, a tunable filter is implemented using one or more controllable capacitors formed on a semiconductor die and using one or more shielded integrated inductors formed on a secondary circuit board that attaches to a carrier circuit board. Additionally, the shielded integrated inductors are formed from patterned metallization layers of the secondary circuit board, and shielding is provided on the secondary circuit board and/or the carrier circuit board to shield the inductors from the semiconductor die and/or other components.

Abstract: A wireless mesh network system includes network nodes that operate in blink and canopy modes of operation. In operation, a network manager joins nodes operating in the canopy node to the network and allocates network bandwidth to the canopy nodes. The allocated bandwidth includes a first bandwidth allocated for transmitting and receiving data packets between canopy nodes that are joined to the network, and a second bandwidth allocation for receiving network joining messages from nodes that are not joined to the network. The second bandwidth allocation is also used for receiving data messages from nodes operating in the blink mode. Thus, in response to receiving a message that was transmitted from a blink node to a canopy node using the second bandwidth allocation, the network manager identifies the message as a data message and provides the data from the message to a host application.

Abstract: Techniques are described to slow the turn off of a pass transistor coupled to an inductive load and being controlled by a hot swap or switch controller in the event of a fault on the load side. Active circuitry can control the gate of the pass transistor, e.g., field-effect transistor (FET), as the inductive load de-energizes and a feedback loop can servo the gate voltage of the pass transistor in order to ensure that its source does not go below a reference voltage.

Abstract: Apparatus and methods for control and calibration of tunable filters are provided. In certain embodiments, a tunable filter includes at least one controllable component (for instance, a controllable inductor or a controllable capacitor) having a value that changes or adjusts a center frequency of the tunable filter. For example, the controllable component can correspond to a controllable inductor or a controllable capacitor of an inductor-capacitor (LC) resonator of the tunable filter. The tunable filter further includes a control circuit implemented with an approximation function for estimating a value of the controllable component for achieving a desired center frequency indicated by a frequency control signal.

Abstract: A MEMS device is provided comprising a substrate; a proof mass coupled to the substrate and configured to move along a resonator axis; a drive structure comprising at least one electrode and configured to drive the proof mass to move along the resonator axis; and a pivoting linkage coupled to the proof mass at first and second ends of the pivoting linkage, the first end comprising a first fixed pivot and the second end comprising a second fixed pivot, the pivoting linkage comprising: a first bar configured to pivot about the first fixed pivot and a first dynamic pivot; a second bar configured to pivot about the second fixed pivot and a second dynamic pivot; and a third bar configured to pivot about the first dynamic pivot and the second dynamic pivot, wherein the proof mass moves along the resonator axis when the pivoting linkage pivots.

Abstract: A MEMS device is provided comprising a mass configured to move along a first axis and a second axis substantially perpendicular to the first axis; a drive structure coupled to the mass and configured to cause the mass to move along the first axis; a sense structure coupled to the mass and configured to detect motion of the mass along the second axis; a stress relief structure coupled to one of the drive structure or the sense structure; and at least one anchor coupled to an underlying substrate of the MEMS device, wherein the stress relief structure is coupled to the at least one anchor and the at least one anchor is disposed outside of the stress relief structure.

Abstract: A stress-isolated microelectromechanical systems (MEMS) device and a method of manufacture of the stress-isolated MEMS device are provided. MEMS devices may be sensitive to stress and may provide lower performance when subjected to stress. A stress-isolated MEMS device may be manufactured by etching a trench and/or a cavity in a first side of a substrate and subsequently forming a MEMS device on a surface of a platform opposite the first side of the substrate. Such a stress-isolated MEMS device may exhibit better performance than a MEMS device that is not stress-isolated. Moreover, manufacturing the MEMS device by first forming a trench and cavity on a backside of a wafer, before forming the MEMS device on a suspended platform, provides increased yield and allows for fabrication of smaller parts, in at least some embodiments.

Abstract: Systems and methods for performing calibration of antenna arrays with dual-polarization antenna elements are disclosed. An example system includes an antenna array and a calibration circuitry. The antenna array includes a plurality of antenna cells arranged in K rows and L columns, each cell including a plurality of dual-polarization antenna elements. Antenna cells in columns 1 through Y form a first sub-array, while antenna cells in columns Y+1 through L form a second sub-array. The calibration circuitry is configured to perform calibration by individually calibrating each column of antenna cells of the first sub-array, calibrating different columns of antenna cells of the first sub-array with respect to one another, individually calibrating each column of antenna cells of the second sub-array, calibrating different columns of antenna cells of the second sub-array with respect to one another, and calibrating antenna elements of the first and second sub-arrays with respect to one another.

Abstract: Columnar multi-axis microelectromechanical systems (MEMS) devices (such as gyroscopes) balanced against undesired linear and angular vibration are described herein. In some embodiments, the columnar MEMS device may comprise at least two multiple-mass columns, each having at least three proof masses and being configured to sense rotation about a respective axis. The motion and mass of the proof masses may be controlled to achieve linear and rotational balancing of the MEMS device. The columnar MEMS device may further comprise one or more modular drive structures disposed alongside each multiple-mass column to facilitate displacement of the proof masses of a respective column. The MEMS devices described herein may be used to sense roll, yaw, and pitch angular rates.

Abstract: System and apparatus for measuring biopotential and implementation thereof. A device for mitigating electromagnetic interference (EMI) thereby increasing signal-to-noise ratio is disclosed. Specifically, the present disclosure relates to an elegant, novel circuit for measuring a plurality of biopotentials in useful in a variety of medical applications. This allows for robust, portable, low-power, higher S/N devices which have historically required a much bigger footprint.

Abstract: Techniques for improving current sensing via a shunt resistance are provided. In an example, an apparatus for sensing current can include a substrate, and a plurality of metal layers stacked on the substrate and separated from the substrate and from each other by an insulation material. In certain examples, a first one or more metal layers can form a sense resistance configured to pass current between a source and a load, and a second one or more metal layers can form one or more gain resistances coupled to the sense resistance and configured to couple to a current sense amplifier. In some example, a metal layer can include portions of both the sense resistance and the gain resistance to compensate for environmental anomalies, material anomalies or manufacturing anomalies.

Abstract: Aspects of this disclosure relate to detecting and recording information associated with electrical overstress (EOS) events, such as electrostatic discharge (ESD) events. For example, in one embodiment, an apparatus includes an electrical overstress protection device, a detection circuit configured to detect an occurrence of the EOS event, and a memory configured to store information indicative of the EOS event.

Abstract: Aspects of this disclosure relate to controlling one or more vehicle systems based on a determined weather condition. In some embodiments, a radar system can be mounted on a vehicle and can collect weather data by receiving electromagnetic signals. A weather condition can be determined based on the collected weather data, and a vehicle system can be controlled based on the determined weather condition, such as vehicle lighting, windscreen wipers, or cruise control. In some embodiments, weather conditions can include fog, sleet, or smog. The weather condition can be determined by analyzing scattered reflections from incident microwaves and/or radio waves to determine a level of attenuation of the scattered electromagnetic energy indicative of a presence or absence of particles. A map can be displayed displaying the weather condition and controlling vehicle navigation systems. The collected weather data can be compared with data from a LiDAR or camera system for reliability.

Abstract: Various examples are directed to systems and methods for managing a sensor. A measurement system may receive, from a host device, a first register map describing a first configuration of a measurement system. The first configuration may be associated with a first sensor. The measurement system may compare the first register map to an error rule set indicating inconsistent register map arrangements. After comparing the first register map to the error rule set, the measurement system may configure a switch matrix of the measurement system to sample the first sensor according to the first configuration of the measurement system. The measurement system may receive a plurality of samples from a first sensor and generate first digital measurement data based at least in part on the plurality of samples.

Abstract: Columnar multi-axis microelectromechanical systems (MEMS) devices (such as gyroscopes) balanced against undesired linear and angular vibration are described herein. In some embodiments, the columnar MEMS device may comprise at least two multiple-mass columns, each having at least three proof masses and being configured to sense rotation about a respective axis. The motion and mass of the proof masses may be controlled to achieve linear and rotational balancing of the MEMS device. The columnar MEMS device may further comprise one or more modular drive structures disposed alongside each multiple-mass column to facilitate displacement of the proof masses of a respective column. The MEMS devices described herein may be used to sense roll, yaw, and pitch angular rates.

Abstract: Techniques for efficient operation of a linear stage in an H-bridge system are provided. In an example, a linear stage can switch between voltage regulation and current regulation over a range of a command signal. The particular regulation mode can depend on the regulation mode of a switched stage of the H-bridge system. Efficiency can be realized by using current regulation of the linear stage when the output voltage of the linear stage moves away from the voltage of a supply rail. Such a control scheme can reduce the voltage across the linear stage for a larger range of the command signal resulting in less heat dissipation of the linear stage compared to conventional control of H-bridge linear stages.

Abstract: Techniques are provided for segmented windings of a coupled inductor within a DC-DC voltage converter or regulator. In an example, a coupled inductor circuit can include a first winding comprising a conductive coil having a central axis, and a second winding configured to magnetically couple with the first winding. The second winding can have a plurality of individual segments. Each individual segment can form a fraction of one turn of the second winding. Each segment can include a first conductor, a ground conductor, and a first switch to selectively couple, and selectively isolate, the first conductor and the ground conductor.

Abstract: Techniques for an isolated DC-DC converter are provided. In an example, a method of operating an isolated DC-DC converter can include inducing a first, primary current flow in primary windings of a first transformer and a second transformer during a first interval, inducing a second, primary current flow in the primary windings during a second interval, freewheeling current of the primary windings via a ground connection of the primary windings during transitions between the first interval and the second interval, and repeatedly alternating between the first interval and the second interval to generate a single DC output voltage using a secondary winding of the first transformer and a secondary winding of the second transformer.