Abstract: A method includes extracting, from multiple microphone input, a hyperset of features of acoustic sources, using the extracted features to identify separable clusters associated with acoustic scenarios, and classifying subsequent input as one of the acoustic scenarios using the hyperset of features. The acoustic scenarios include a desired spatially moving/non-moving talker, and an undesired spatially moving/non-moving acoustic source. The hyperset of features includes both spatial and voice biometric features. The classified acoustic scenario may be used in a robotics application or voice assistant device desired speech enhancement or interference signal cancellation. Specifically, the classification of the acoustic scenarios can be used to adapt a beamformer, e.g., step size adjustment. The hyperset of features may also include visual biometric features extracted from one or more cameras viewing the acoustic sources.

Abstract: An apparatus for calibrating a differential circuit that includes a differential integrator having an input, a gain, and an output connected to a comparator. The differential integrator output is chargeable to a threshold prior to an integration period. The differential integrator integrates the input during the integration period such that the differential integrator output goes toward zero from the threshold. The comparator detects the output of the differential integrator reaching zero. The apparatus includes a closed-loop gain trim circuit to perform a coarse calibration to adjust and set the gain of the differential integrator and a reference generator that generates the threshold to which the differential integrator output is pre-charged. The reference generator is trimmable during a fine calibration to adjust and set the threshold to correct for residual gain error in the differential circuit remaining after the coarse calibration is performed.

Abstract: An acoustic crosstalk canceller is determined for an asymmetric audio playback device, by determining a transfer function of an acoustic stereo playback path having asymmetries defined by speakers of the playback device. The transfer function is inverted to determine an inverse transfer function. The inverse transfer function is regularised by applying frequency dependent regularisation parameters to obtain an acoustic crosstalk canceller. Also, the inverse transfer function could be regularised for symmetric playback paths by applying aggregated frequency dependent regularisation parameters to obtain an acoustic crosstalk canceller without band branching.

Abstract: An audio processing system is described for an audio event detection (AED) system. The system includes a feature extraction block configured to derive at least one feature which represents a spectral feature of the input signal.

Abstract: A single-bit audio stream can be converted to a modified single-bit audio stream with a constant edge rate while maintaining a modulation index of the original audio stream using direct mapping. With direct mapping, a pre-filter bank may be combined with a multi-bit symbol mapper to select symbols for the modified audio stream with a constant edge rate per symbol and the same modulation index as the original audio stream. The output of the pre-filter bank may be an audio stream with no consecutive full-scale symbols. Using the output of the pre-filter bank, a multi-bit symbol mapper may use the symbol selector to output a symbol with a constant edge rate per symbol and the same modulation index as the original signal. The symbols may be converted to an analog signal for reproduction of audio content using a transducer.

Abstract: A bass enhancement may be applied to improve the perception of low-frequency sounds by a user of an electronic device. A distortion function may be applied to the audio signal that results in creation of higher frequency content related to the low-frequency sounds. This higher frequency content may be interpreted by a listener's ear in a similar manner as the low-frequency sounds. The distortion function may be a Sigmoid function. Bass enhancements may also include scaling of the audio signal prior to distortion, adaptation of the distortion, or gap band filtering prior to the distortion.

Abstract: The present disclosure relates to Class D amplifier circuitry comprising: an input for receiving an input signal; first and second output nodes for driving a load connected between the first and second output nodes. A first driver stage is provided for switching the first node between a first supply rail and a second supply rail, and a second driver stage is provided for switching the second node between the first supply rail and the second supply rail. The Class D amplifier circuitry also includes first driver control circuitry configured to receive a first carrier wave and control the switching of the first driver stage based in part on the first carrier wave; second driver control circuitry configured to receive a second carrier wave and control the switching of the second driver stage based in part on the second carrier wave; and a carrier wave generator configured to provide the first carrier wave and the second carrier wave.

Abstract: A method and apparatus for programming a one-time programmable (OTP) memory device is disclosed that allows for resuming and recovering from an interrupted programming cycle (e.g. due to loss of power or user interaction). Upon re-initiation of a programming cycle with the same memory range, a programming controller may detect the memory address where interruption occurred, and resume programming from that address. If the programming interruption resulted in an incorrectly programmed word at the interrupted address, a word repair register may be mapped to the corrupted address to enable correction of that word. The remainder of the memory range may then be programmed normally.

Abstract: A system may include a resonant phase sensing system comprising a resistive-inductive-capacitive sensor and a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor, and a compensation circuit. The measurement circuit may be configured to use a phase detector to measure phase information associated with the resistive-inductive-capacitive sensor and based on the phase information, determine a displacement of a metal plate relative to the resistive-inductive-capacitive sensor. The compensation circuit may be configured to detect a change in a physical property associated with the resistive-inductive-capacitive sensor other than the displacement and compensate the phase information to correct for the change in the physical property.

Abstract: A system may include a resistive-inductive-capacitive sensor, a driver configured to drive the resistive-inductive-capacitive sensor at a driving frequency, a measurement circuit communicatively coupled to the resistive-inductive-capacitive sensor and configured to measure phase information and amplitude associated with the resistive-inductive-capacitive sensor, and a noise detection circuit communicatively coupled to the measurement circuit and configured to determine a presence of external interference in the system based on at least one of the phase information and the amplitude information.

Abstract: The disclosure relates in general to on-ear transition detection, and in particular to on-ear transition detection circuitry comprising: a monitoring unit operable to monitor a speaker current flowing through a speaker and/or a speaker voltage induced across the speaker, and to generate a monitor signal indicative of the speaker current and/or the speaker voltage; and an event detector operable to detect a qualifying disturbance in a sensor signal indicative of a qualifying pressure change incident on the speaker caused by the speaker transitioning from an on-ear state to an off-ear state or vice versa, wherein the sensor signal is, or is derived from, the monitor signal.

Abstract: An amplifier includes input transconductors that receive an input signal, the input signal having a voltage swing. A supply side current mirror generates a gate voltage as a function of input signal voltage and current sources that provide a bias current of the input transconductors as a function of the gate voltage to maintain a constant bias current across the voltage swing of the input signal. Resistors average source voltages of the transconductance-cancelling transconductors to provide an average source voltage and apply the average source voltage to wells of input devices of the transconductance-cancelling transconductors to reduce back bias effect. The input devices are laid out in a same well and have a common centroid to cancel out process mismatches. A first I-DAC trims an offset of first transconductors, and a second I-DAC trims an offset of second transconductors to attain low offsets across a rail-to-rail input common mode range.

Abstract: A method may include receiving an input signal from a force sensor configured to sense a force associated with a human interaction with a virtual button, comparing the input signal to at least one behavioral model, the at least one behavioral model comprising one or more parameters associated with a valid human interaction with the virtual button, and determining whether a valid human interaction with the virtual button occurred based on the comparing.

Abstract: A biometric is formed for at least one enrolled speaker by: obtaining a sample of speech of the enrolled speaker; obtaining a measure of a fundamental frequency of the speech of the enrolled speaker in each of a plurality of speech frames; and forming a first distribution function of the fundamental frequency of the speech of the enrolled speaker. Subsequently, for a speaker to be recognised, a sample of speech of the speaker to be recognised is obtained. Then, a measure of a fundamental frequency of the speech of the speaker to be recognised is obtained in each of a plurality of speech frames. A second distribution function of the fundamental frequency of the speech of the speaker to be recognised is formed, the second distribution function and the first distribution function are compared, and it is determined whether the speaker to be recognised is the enrolled speaker based on a result of comparing the second distribution function and the first distribution function.

Abstract: A mobile device may include a power supply configured to generate a supply voltage, a power converter configured to generate a converted voltage from the supply voltage wherein the converted voltage is significantly different than the supply voltage, and a plurality of power domains. The plurality of power domains may include a first power domain global to the mobile device and comprising a first plurality of electronic components powered from the supply voltage and a second power domain global to the mobile device and comprising a second plurality of electronic components powered from the converted voltage, wherein power requirements of each of the second plurality of electronic components are significantly higher than power requirements of each of the first plurality of electronic components.

Abstract: A method of speaker identification, comprises: receiving an audio signal representing speech; removing effects of a channel and/or noise from the received audio signal to obtain a cleaned audio signal; obtaining an average spectrum of at least a part of the cleaned audio signal; and comparing the average spectrum with a long term average speaker model for an enrolled speaker. Based on the comparison, it can be determined whether the speech is the speech of the enrolled speaker.

Abstract: A driver system may include a first n-type field-effect transistor coupled at its non-gate terminals between an output of the driver system and a first terminal of a supply voltage and configured to drive the output when the first n-type field-effect transistor is activated, a second n-type field-effect transistor coupled at its non-gate terminals between an output of the driver system and a second terminal of the supply voltage and configured to drive the output when the second n-type field-effect transistor is activated, a high-side capacitor coupled to the output of the driver system, and a low-side capacitor coupled to the second terminal of the supply voltage, wherein the high-side capacitor and the low-side capacitor are configured to track and correct for mismatches between a first resistance of the first n-type field-effect transistor and a second resistance of the second n-type field-effect transistor.

Abstract: An apparatus for providing an output signal to an audio transducer comprises: one or more signal paths for receiving respective digital audio input signals, applying respective digital gains, and outputting respective amplified digital audio input signals; one or more inputs for receiving one or more volume parameters associated with the digital audio input signals; converter circuitry, coupled to the one or more signal paths, for converting the one or more amplified digital audio input signals into the analogue domain, and outputting an analogue audio input signal; an analogue gain element, for applying an analogue gain to the analogue audio input signal and outputting the output signal; and a control circuit, coupled to the one or more signal paths, operative to select the analogue gain based on a comparison of the volume parameters and the one or more digital audio input signals as multiplied by the volume parameters, and to select the respective digital gains for each digital audio input signal so that an

Abstract: Embodiments described herein provide methods and apparatus for outputting a haptic signal to a haptic transducer. A method comprises storing a representation of a part of the haptic signal comprising a first information point indicating a first amplitude and at least one first frequency of the part of the haptic signal at a first time, wherein the representation is associated with a user experience; responsive to receiving an indication of occurrence of the user experience, determining the haptic signal based on the first information point such that the part of the haptic signal has the first amplitude and the at least one first frequency at the first time. The method may further comprise outputting the haptic signal to the haptic transducer.

Abstract: An apparatus measures a speaker impedance. A DAC converts a known digital input signal to an audio frequency first analog voltage signal. Resistors with known resistance attenuate the first analog voltage signal to generate a current. The known resistance effectively determines the current because the known resistance is high relative to the speaker impedance. The current is sourced into the speaker to generate a second analog voltage signal. The known resistance is sufficiently high to cause the second analog voltage signal to be inaudible as transduced by the speaker. An amplifier amplifies the second analog voltage signal with a known gain to generate a third analog voltage signal. An ADC converts the third analog voltage signal to a digital output signal. A processing element calculates the impedance of the speaker proportional to the digital output signal based on the known digital input signal, the known resistance, and the known gain.