Abstract: In one example, a calibration method includes receiving, from a sensor proximate a first conductor, a sensor signal representing a measurement of a magnetic field produced based on a first current flowing in the first conductor and a second current flowing in a second conductor, the first current including first and second current components having different frequencies, and the second current including third and fourth current components, the third current component phase shifted from, and having the same frequency as, the first current component and the fourth current component having a different frequency from the third current component, determining reference values of the first and second currents, and based on the sensor signal and the reference values of the first and second currents, determining for the sensor, a plurality of coupling coefficients representing magnetic field coupling between the first and second conductors.

Abstract: In some examples, an apparatus comprises a first coil, a second coil, a control circuit, and a processing circuit. The second coil is magnetically coupled to the first coil. The control circuit has a signal output coupled to the first coil, and a control output, and the control circuit configured to: responsive to a state of the control input, select a field strength level from a set of discrete field strength levels; and provide a first signal representing the selected field strength level at the signal output. Also, the processing circuit has processing inputs and a processing output, the processing inputs coupled to the second coil, the processing output coupled to the control input, and the processing circuit configured to, responsive to a second signal across the processing inputs, set a state of the processing output representing a polarity of a magnetic field sensed by the second coil.

Abstract: An avalanche photo-diode (APD) circuit includes a first APD and a bias circuit. The first APD is configured to detect light. The bias circuit is configured to control a gain of the first APD. The bias circuit includes a second APD, a reference voltage source, a bias voltage generation circuit, and a metal layer configured to shield the second APD from the light. The reference voltage source is configured to bias the second APD. The bias voltage generation circuit is configured to generate a bias voltage for biasing the first APD based on dark current output by the second APD.

Abstract: A pulsed light source illuminates a scene with a virtual array of points. Light reflected by the scene is detected by a small pixel array, allowing generation of a three-dimensional map of the scene. A processing element processing data output by the small pixel array uses a multipath resolution algorithm to resolve individual objects in the scene.

Abstract: A pulsed light source illuminates a scene with a virtual array of points. Light reflected by the scene is detected by a small pixel array, allowing generation of a three-dimensional map of the scene. A processing element processing data output by the small pixel array uses a multipath resolution algorithm to resolve individual objects in the scene.

Abstract: Disclosed examples include methods and systems to measure fluid flow, including a transmit circuit to provide a transducer transmit signal based on a transmit pulse signal, a receive circuit to receive a transducer receive signal, an ADC to sample a receive signal from the receive circuit and provide a sampled signal, and a processing circuit that computes a transit time based on the sampled signal, and provides the transmit pulse signal including a first portion with a frequency in a first frequency band, and a second portion with a second frequency outside the first frequency band to mitigate undesired transducer vibration, where the second frequency is outside a transducer frequency bandwidth of the transducer.

Abstract: An avalanche photo-diode (APD) circuit includes a first APD and a bias circuit. The first APD is configured to detect light. The bias circuit is configured to control a gain of the first APD. The bias circuit includes a second APD, a reference voltage source, a bias voltage generation circuit, and a metal layer configured to shield the second APD from the light. The reference voltage source is configured to bias the second APD. The bias voltage generation circuit is configured to generate a bias voltage for biasing the first APD based on dark current output by the second APD.

Abstract: A transducer system with transducer and circuitry for applying a pulse train at a single frequency to excite the transducer. The transducer is operable to receive an echo waveform in response to the pulse train. The system also comprises circuitry for determining a time of flight as between a first reference time associated with the pulse train and a second reference time associated with the echo waveform.

Abstract: A system for driving an audio speaker that has an impedance, the system comprising: a scaler having an analog input and a scaler output that is an attenuated analog input; an amplifier having an amplifier input coupled to the scaler output and an amplifier output; a current sensor having a sensor input coupled to the speaker and a sensor output, the current sensor configured to generate a sensor signal at the sensor output responsive to a current from the audio speaker; and a compensator circuit having a circuit input coupled to the sensor output and a circuit output coupled to the amplifier input, the compensator circuit configured to supply a compensation signal to the amplifier input by applying a transfer function to the sensor signal.

Abstract: An apparatus is provided. In the apparatus, there is an antenna package and an integrated circuit (IC). A circuit trace assembly is secured to the IC. A coupler (with an antenna assembly and a high impedance surface (HIS)) is secured to the circuit trace assembly. An antenna assembly has a window region, a conductive region that substantially surrounds the window region, a circular patch antenna that is in communication with the IC, and an elliptical patch antenna that is located within the window region, that is extends over at least a portion of the circular patch antenna, and that is in communication with the circular patch antenna. The HIS substantially surrounds the antenna assembly.

Abstract: A transducer system with transducer and circuitry for applying a pulse train at a single frequency to excite the transducer. The transducer is operable to receive an echo waveform in response to the pulse train. The system also comprises circuitry for determining a time of flight as between a first reference time associated with the pulse train and a second reference time associated with the echo waveform.

Abstract: A first amplifier has an input to receive a Hall-signal output current from a first Hall element and has an output to output feedback current in response to the received Hall-signal output current. The Hall-signal output current is impeded by an impedance of the first Hall element. The feedback current is coupled to counterpoise the Hall-signal output current at the input, and a voltage at the output is an amplified Hall output signal. A second amplifier generates a high-frequency portion output signal in response to a difference between the amplified Hall output signal and a Hall-signal output signal from a second Hall element. A filter reduces high-frequency content of the high-frequency portion output signal and generates an offset correction signal. A third amplifier generates a corrected Hall signal in response to a difference between the amplified Hall output signal and the offset correction signal.

Abstract: A system for driving an audio speaker that has an impedance, the system comprising: a scaler having an analog input and a scaler output that is an attenuated analog input; an amplifier having an amplifier input coupled to the scaler output and an amplifier output; a current sensor having a sensor input coupled to the speaker and a sensor output, the current sensor configured to generate a sensor signal at the sensor output responsive to a current from the audio speaker; and a compensator circuit having a circuit input coupled to the sensor output and a circuit output coupled to the amplifier input, the compensator circuit configured to supply a compensation signal to the amplifier input by applying a transfer function to the sensor signal.

Abstract: A first amplifier has an input to receive a Hall-signal output current from a first Hall element and has an output to output feedback current in response to the received Hall-signal output current. The Hall-signal output current is impeded by an impedance of the first Hall element. The feedback current is coupled to counterpoise the Hall-signal output current at the input, and a voltage at the output is an amplified Hall output signal. A second amplifier generates a high-frequency portion output signal in response to a difference between the amplified Hall output signal and a Hall-signal output signal from a second Hall element. A filter reduces high-frequency content of the high-frequency portion output signal and generates an offset correction signal. A third amplifier generates a corrected Hall signal in response to a difference between the amplified Hall output signal and the offset correction signal.

Abstract: A pulsed light source illuminates a scene with a virtual array of points. Light reflected by the scene is detected by a small pixel array, allowing generation of a three-dimensional map of the scene. A processing element processing data output by the small pixel array uses a multipath resolution algorithm to resolve individual objects in the scene.

Abstract: In described examples, a Hall effect sensor includes a primary Hall effect sensor element and an auxiliary Hall effect sensor element. A known magnetic field is applied to the auxiliary Hall effect sensor to produce an auxiliary Hall voltage used in a feedback loop to control the bias current of the auxiliary Hall effect sensor to maintain the auxiliary Hall voltage approximately constant over a range of temperature and other factors. A bias current for the primary Hall effect sensor is controlled to track the bias current of the auxiliary Hall effect sensor to maintain the sensitivity of the primary Hall effect sensor approximately constant over the same range of temperature and other factors.

Abstract: One example includes a system that is comprised of a speaker, an amplifier, a current sensor, and a compensator circuit. The speaker produces audio in response to an amplified analog input signal received at a speaker input. The amplifier receives an analog audio input signal and provides the amplified analog audio input signal to the speaker input. The current sensor senses current passing through the speaker and provides a current sensor signal indicative thereof. The compensator circuit applies a transfer function to the current sensor signal to provide a compensation signal as feedback into the analog audio input signal, the transfer function matching at least one of resistance and inductance of the speaker.

Abstract: One example includes a current measurement system. The system includes at least two magnetic field sensors positioned proximal to and in a predetermined arrangement with respect to a current conductor, each of the magnetic field sensors being configured to measure magnetic field associated with a current flowing in the current conductor and provide respective magnetic field measurements. The system also includes a current measurement processor configured to implement a mathematical algorithm based on a Taylor series expansion of the magnetic field measurements to calculate an amplitude of the current based on the mathematical algorithm.

Abstract: A system for error correction code (ECC) management of write-once memory (WOM) codes includes, for example, a controller for selecting between one of a WOM (Write-Once Memory) mode and an ECC (error correction code) mode. A codec is arranged to operate in the selected mode. The codec while operating in the ECC mode is arranged to identify a bit position of at least one bit error in response to ECC parity bits of a first received data word. The codec while operating in the WOM mode is arranged to receive a WOM-encoded word from an addressed location in a WOM device, to receive a second received data word to be encoded and written to the addressed location, and to generate WOM-encoded word for writing to the addressed location in the WOM device. The WOM-encoded word for writing to the addressed location is optionally ECC encoded.

Abstract: Read-only (“RO”) data consisting of a physically unclonable function (“PUF”) pattern is written to a ferroelectric random-access memory (“FRAM”) memory array. The FRAM array is baked to imprint the PUF pattern with a selected average depth of imprint and a corresponding average read reliability. The average depth of imprint and corresponding average read reliability are determined during testing after baking. The PUF pattern as read after baking is compared to the PUF pattern as written prior to baking. Additional PUF pattern writing and baking cycles may be performed until the average depth of imprint and associated read reliability reach a first selected level. Integrated circuits determined to be over-imprinted by exceeding a second selected level may be rejected. The first and second levels of PUF pattern imprint are selected such as to produce FRAM arrays with a unique fingerprint for each individual FRAM array-containing integrated circuit.