Abstract: Techniques for sensing position using a magnetic field direction sensor are provided. In an example, a system can include a magnet, a first magnetic field direction sensor, positioned between the magnet and a magnetic feature of a first structure, the sensor configured to move with the magnet and to measure a direction of a magnetic field produced by the magnet relative to a first axis (x). In certain examples, the magnetic feature is configured change position with respect to the magnetic sensor along the first axis (x) as a relative position between the magnet and the magnetic feature changes with respect to a second axis (y).

Abstract: A plurality of lower voltage metal oxide semiconductor sensors are integrated and distributed in various parts of a power MOSFET to provide over temperature protection. The sensors are sensitive to temperatures of the various parts of the power MOSFET and configured to regulate the power MOSFET when a trip temperature is reached by reducing the operation of the MOSFET. A bias network is configured to set the trip temperature. In some configurations, a threshold voltage is used to monitor and control the maximum temperature.

Abstract: System and apparatus for portable gas detection. Specifically, this disclosure describes apparatuses and systems for optical gas detection in a compact package. There is a need for a very compact, low-power, gas detection system for gases such as CO2, NOx, water vapor, methane etc. This disclosure provides an ultra-compact and highly efficient optical measurement system based on principals of optical absorption spectroscopy. It reduces the size of the instrument as well its power consumption by more than an order of magnitude making it possible to deploy it widely. There is an identified need for large number of distributed gas sensors to improve human health, environment, and save energy usage.

Abstract: An electronic circuit comprises a primary amplifier circuit including a differential input and an output, an offset nulling amplifier circuit, and an impedance matching circuit. The offset nulling amplifier circuit includes a differential input and an output. The differential input of the primary amplifier circuit is operatively coupled to a differential input of the offset nulling amplifier circuit and the impedance matching circuit. The output of the offset nulling amplifier circuit is operatively coupled to the primary amplifier circuit and provides a voltage to reduce offset in an output signal of the primary amplifier circuit.

Abstract: Systems and methods are provided for an automatic exposure detection feature for adding to an x-ray panel readout device, including an imaging panel having a low power mode, a sense circuit for receiving an input signal in the low power mode and restricting an input signal voltage to a first voltage, and a sensor for sensing a change in the input signal voltage, wherein the change in input signal voltage indicates exposure to an x-ray signal.

Abstract: This application discusses techniques for providing sensorless rotor position information of a multiple phase motor without using predetermined motor parameters or models, other than the number of phases of the motor. In certain examples, motor rotor position information can be provided using samples of current from zero-voltage vectors of the motor windings.

Abstract: Various examples are directed to integrated circuits and/or controllers for battery packs. An integrated circuit for managing at least a portion of a battery pack comprises a first cell controller. The first cell controller may comprise a first switch system, a first local controller, a first receive terminal to receive a first command from a preceding cell controller, and a first transmit terminal to send the first command to a succeeding cell controller. The first switch system may comprise two pairs of switches to couple a first battery cell to a pair of output terminals in an H-bridge configuration. The first local controller may control the first switch system to selectively connect and disconnect the first battery cell to the pair of output terminal.

Abstract: Aspects of the present disclosure relate to decoding the output of a multi-turn magnetic sensor using a successive approximation technique to detect a number of turns of a magnetic target. A decoder circuit can decode a turn count of the multi-turn magnetic sensor by obtaining measurements at nodes that are determined from values of previous measurements.

Abstract: System and apparatus for carbon dioxide detection within an automobile. Specifically, this disclosure describes apparatuses and systems for optical gas detection in a stationary and moving vehicle. There is a need for a such a system to prevent loss of life and contribute to a safer traffic environment. This disclosure provides a highly efficient optical measurement system based on principals of optical absorption spectroscopy. It detects the presence of neglected children and animals and changes the vehicle's interior environment accordingly so as to preclude many potentially dangerous conditions. The present disclosure can also optimize ventilation for a driver. To this end, a driver can maximize alertness and attentiveness.

Abstract: Random chopping is an effective technique for data converters. Random chopping can calibrate offset errors, calibrate offset mismatch in interleaved ADCs, and dither even order harmonics. However, the non-idealities of the (analog) chopper circuit can limit its effectiveness. If left uncorrected, these non-idealities cause severe degradation in the noise floor that defeats the purpose of chopping, and the non-idealities may be substantially worse than the non-idealities that chopping is meant to fix. To address the non-idealities of the random chopper, calibration techniques can be applied, using correlators and calibrations that may already be present for the data converter. Therefore, the cost and digital overhead are negligible. Calibrating the chopper circuit can make the chopping more effective, while relaxing the design constraints imposed on the analog circuitry.

Abstract: Herein disclosed is a system that may be implemented within a headphone to facilitate hearing testing. Implementation of the system in the headphone may include implementation of tone generation circuitry and sound pressure level measurement circuitry being implemented in the headphone limiting the amount of calibration for accurate measurement when performing a hearing test.

Abstract: Actuators are used to move a variety of objects to desired positions. It is generally desirable that they can do this quickly without exhibiting overshoot or ringing. Some actuators are required to respond very quickly and examples of these are voice coil drivers used to move lenses in autofocus cameras provided in everyday devices such as smart phones and tablets. A rapid two step controller scheme had already been disclosed by Analog Devices Inc. While the scheme works well, it can only be used reliably if the resonant frequency of the actuator is known to within 2 or 3%. The inventors have discovered that the resonant frequency of an actuator unexpectedly changes as a function of position. This disclosure provides ways of modifying the control scheme to cope with changes in resonant frequency.

Abstract: The present disclosure provides alternative solutions to the problem of providing a stable voltage reference to high speed ADCs that possess high sampling rates. In one example the high speed amplifier is replaced by a smaller, slower, lower power amplifier in combination with a relatively large capacitor connected to the same node as the amplifier output and the ADC reference input. The capacitor is charged substantially to the external reference voltage and hence keeps the reference input of the ADC almost at the external reference voltage between conversions, such that when conversion is about to occur and the external reference is switched in then very little charge is required from the external reference, and hence the reference signal quickly settles.

Abstract: An apparatus for processing radio frequency (RF) signals includes a housing with a cavity. In the cavity, a stripline is configured to carry the RF signal. The stripline is on a substrate and suspended in the cavity. One or more coupled lines, which can be forward and reverse directional microstrip couplers, are electromagnetically coupled to the stripline and receive an attenuated version of the RF signal. The couplers can have a stair step design or asymmetric design to enhance directivity.

Abstract: An microelectromechanical switch uses electrostatic attraction to draw a beam toward a contact and electromagnetic repulsion to disengage and repel the beam from the contact. The electrostatic attraction is generated by a gate electrode. The electromagnetic repulsion is generated between the beam and a magnetic coil positioned on the same side of the beam as the contact. The magnetic coil produces a magnetic field, which induces a current in the beam that repels the magnetic coil. The gate electrode and the magnetic coil may be co-planar or in different planes. A circuit may also operate a coil-shaped structure act as the gate electrode and the magnetic coil, depending on the configuration.

Abstract: A high-voltage (HV) compound switch can include coupling circuitry to help provide better slew rate (dV/dt) control, such as to limit electromagnetic energy radiation during switching, which can cause undesirable EMI. Further, efficiency and on-state resistance can be improved by controllably forward-biasing the “normally on” JFET when the compound switch is in an “on” state. In such an on-state, the JFET temperature can be monitored, such as by monitoring the gate-source junction voltage or the gate current of the JFET. Such temperature information can be used for control or other purposes.

Abstract: There is disclosed in one example a digital phase-locked loop (DPLL) circuit adapted to avoid loop-bandwidth tradeoff, the circuit including: a frequency dimension frequency detector having an external frequency input and a feedback frequency input, the frequency dimension frequency detector including circuitry to measure a frequency difference between the external frequency input and the feedback frequency input and to drive an impulse signal, wherein the impulse signal is of a first species if the difference is positive and of a second species if the difference is negative; and a number-controlled oscillator (NCO) including circuitry to drive an output clock and to adjust the frequency of the output clock responsive to the impulse signal, wherein an output of the NCO provides the feedback frequency input of the frequency dimension frequency detector.

Abstract: One embodiment is a method comprising collecting photoplethysmography (“PPG”) data associated with a user using a biometric monitoring device; extracting a signal quality metric (“SQM”) from the collected PPG data; classifying the PPG data signal based on the extracted SQM into one of a plurality of signal quality levels; and determining based on the classification whether to increase, decrease, or maintain a power level of an LED of the biometric monitoring device.

Abstract: In an optical detection system, received light can be concentrated and presented to a single-pixel photodetector (or an array of relatively few photodetectors). Concentration of received light can be performed by curved concentrator such as a continuously-curved or faceted reflector. A portion or an entirety of the detector might be blinded (e.g., desensitized) by bright interferers such as the sun. An electro-optic shutter such as a liquid crystal (LC) structure can be used to selectively transmit or mask-off portions of the received light. For example, an LC structure can have regions of selectable opacity for a specified polarization of incident light. The LC structure can be controlled to render certain region opaque, such as to suppress interference from unwanted interferers such as the sun, bright lights, or unwanted reflections. An LC structure can also be used to implement a scanned transmit/receive technique.

Abstract: Micro-scale planar-coil transformers including one or more shields are disclosed. The one or more shields can block most common-mode current from crossing from one side to another side of a transformer. Reduction of common-mode current crossing the transformer results in reduction of dipole radiation, which is the main component of electromagnetic interference (EMI) in some transformers.