Abstract: Embodiments of the disclosure relate to methods, apparatus and systems for authentication of a user. The described embodiments relate to obtaining ear biometric data for a user to be authenticated. The ear biometric data comprises one or more features characteristic of the user's ear canal and an associated fit metric indicative of a positioning of a personal audio device relative to the user's ear canal, the personal audio device comprising a transducer for application of acoustic stimulus to the user's ear to obtain the ear biometric data. The user may be identified as a particular authorised user based on one or more features and the associated fit metric.

Abstract: A method of speaker identification comprises receiving an audio signal representing speech; performing a first voice biometric process on the audio signal to attempt to identify whether the speech is the speech of an enrolled speaker; and, if the first voice biometric process makes an initial determination that the speech is the speech of an enrolled user, performing a second voice biometric process on the audio signal to attempt to identify whether the speech is the speech of the enrolled speaker. The second voice biometric process is selected to be more discriminative than the first voice biometric process.

Abstract: A method of controlling a force sensor system to define at least one button implemented by at least one force sensor, the method comprising: receiving a force sensor input; determining a gradient of the force sensor input; and controlling the force sensor system based on the determined gradient.

Abstract: Embodiments of the disclosure include methods, apparatus and computer programs for detecting the proximity of an ear to an audio device. In one embodiment, the disclosure provides a system for detecting the presence of an ear in proximity to an audio device. The system comprises: an input for obtaining a data signal from the environment of the audio device; and an ear biometric authentication module configured to: compare one or more ear biometric features, extracted from the data signal, to an ear biometric template; and generate a first output indicative of the presence or absence of any ear in proximity to the audio device based on the comparison of the one or more extracted ear biometric features to the ear biometric template.

Abstract: A system may include a power converter comprising at least one stage having a dual anti-wound inductor having a first winding and a second winding constructed such that its windings generate opposing magnetic fields in its magnetic core and constructed such that a coupling coefficient between the first winding and the second winding is less than approximately 0.95 and a current control subsystem for controlling an electrical current through the dual anti-wound inductor, the current control subsystem configured to minimize a magnitude of a magnetizing electrical current of the dual anti-wound inductor to prevent core saturation of the dual anti-wound inductor and regulate an amount of output electrical current delivered by the power converter to the load in accordance with a reference input signal.

Abstract: The present disclosure relates to a computing system. The computing system comprises a data input configured to receive an input data signal, a computation unit having an input coupled with the data input, the computation unit being operative to apply a weight to a signal received at its input to generate a weighted output signal, and a controller. The controller is configured to monitor a parameter of the input signal and/or a parameter of the output signal and to issue a control signal to the computation unit to control a level of accuracy of the weighted output signal based at least in part on the monitored parameter.

Abstract: There is described a two-terminal multi-level memristor element synthesised from binary memristors, which is configured to implement a variable resistance based on unary or binary code words. There is further described a circuit such as a synapse circuit implemented using a multi-level memristor element.

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: This application relates to voltage regulators and, particular, to low-dropout regulators (LDOs). The regulator (300) has an output stage (102) which receives an input voltage (Vin) and outputs an output voltage (Vout) and which includes at least one transistor (103) as an output device configured to pass an output current to the output, based on a drive voltage (V1). A differential amplifier (101) is configured to receive a feedback signal derived from the output voltage and also a reference voltage (REF) to generate an amplifier output to control the drive voltage (V1) to minimise any difference between the feedback signal and the reference voltage. A controller (301) is operable to selectively reconfigure the output stage to provide a change in output current in response to a load activity signal (ACT), which is indicative of a change in load activity that results in a change in load current demand for a load connected, in use, to the output.

Abstract: This application relates to methods and apparatus for driving a transducer with switching drivers. A driver circuit has first and second switching drivers for driving the transducer in a bridge-tied-load configuration, each of the switching drivers having a respective output stage for controllably switching the respective driver output node between high and low switching voltages with a controlled duty cycle. Each of switching drivers is operable in a plurality of different driver modes, wherein the switching voltages are different in said different driver modes. A controller controls the driver mode of operation and the duty cycle of the switching drivers based on the input signal. The controller is configured to control the duty cycles of the first and second switching drivers within defined minimum and maximum limits of duty cycles; and to transition between driver modes of operation when the duty cycle of one of the switching drivers reaches a duty cycle limit.

Abstract: An ambient-aware audio system reduces stationary noise and maintains dynamic environmental sound in a received input audio signal. The system includes a signal-to-noise ratio (SNR) estimator that estimates an a priori SNR and an a posteriori SNR, a gain function that uses the estimated SNRs as inputs to compute coefficients of a frequency domain noise reduction filter that uses the computed coefficients to filter a frame of the input audio signal to generate an output audio signal. The SNR estimator, gain function, and filter are configured to iterate over a plurality of frames of the input audio signal. The SNRs are estimated using the input audio signal and the output audio signal associated with one or more of the plurality of frames. The gain function is derived to minimize an expected value of differences between spectral amplitudes of the output audio signal and the input audio signal.

Abstract: Monitoring circuitry, comprising: a current monitoring unit operable to monitor a speaker current flowing through a speaker and generate a monitor signal indicative of that current; and a controller operable, based on a control signal, to control the current monitoring unit to control whether the monitor signal is generated and/or a property of the monitor signal.

Abstract: A method for screening a semiconductor device for production of excessive random telegraph sequence (RTS) noise includes measuring noise of the semiconductor device at a first temperature, changing the temperature of the semiconductor device to a second temperature different from the first temperature, measuring noise of the semiconductor device at the second temperature, extracting a characteristic of the measured noise at the first and second temperatures (e.g., standard deviation, HMM output, frequency domain spectrum of time domain noise measurement), making a comparison of the extracted first and second noise characteristics, and making a determination whether the semiconductor device produces excessive RTS noise based on whether the comparison is above a predetermined threshold. Two different bias conditions of the device may be employed rather than, or in addition to, the two different temperatures.

Abstract: A method of randomizing inductor current in at least one of a plurality of parallel coupled peak/valley current-controlled power converters may include comparing the inductor current to a threshold to generate a comparison signal, delaying the comparison signal by a plurality of delay amounts to generate a plurality of delayed versions of the comparison signal, and randomly selecting one of the plurality of delayed versions of the comparison signal for controlling the inductor current during one or both of a charging state and a transfer state of the at least one of the plurality of parallel coupled peak/valley current-controlled power converters.

Abstract: Wind noise reduction in microphone signals. A first microphone signal is obtained from a first omnidirectional microphone and, contemporaneously, a second microphone signal is obtained from a second omnidirectional microphone. The first and second microphone signals are mixed to produce an output signal. Mixing involves weighting the first and second microphone signals by respective first and second signal weights to produce respective first and second weighted microphone signals, and summing the first and second weighted microphone signals together to produce the output signal. The first and second signal weights are calculated to minimize the power of the output signal.

Abstract: Circuitry for detecting a capacitive load coupled between a first node and a second node, the circuitry comprising: drive circuitry for applying a first voltage to a first node over a first time period; processing circuitry configured to: measure a second voltage at the first node; and determine that the load is a capacitive load based on the second voltage.

Abstract: Embodiments described herein relate to methods and apparatuses for controlling an operation of a vibrational output system and/or an operation of an input sensor system, wherein the controller is for use in a device comprising the vibrational output system and the input sensor system. A controller comprises an input configured to receive an indication of activation or de-activation of an output of the vibrational output system; and an adjustment module configured to adjust the operation of the vibrational output system and/or the operation of the input sensor system based on the indication to reduce an interference expected to be caused by the output of the vibrational output system on the input sensory system.

Abstract: An integrated circuit may include an output for providing an output signal to a transducer including both a source audio signal for playback to a listener and an anti-noise signal for countering the effect of ambient audio sounds in an acoustic output of the transducer, an error microphone input for receiving an error microphone signal indicative of the output of the transducer and the ambient audio sounds at the transducer, and a processing circuit.

Abstract: A method may include measuring an electrical parameter of an electromagnetic load having a moving mass during the absence of a driving signal actively driving the electromagnetic load, measuring a mechanical parameter of mechanical motion of a host device comprising the electromagnetic load, correlating a relationship between the mechanical parameter and the electrical parameter, and calibrating the electromagnetic load across a plurality of mechanical motion conditions based on the relationship.

Abstract: A baseline unit for use in a sensor system, the sensor system comprising N force sensors which output N sensor signals, respectively, where N?2, the baseline unit configured to: monitor measures of gradients of the respective sensor signals; and, in dependence upon the measures of the gradients, control a stored baseline setting to control how a baseline signal for at least one of said sensor signals is calculated using a baseline-calculation method, the baseline-calculation method configured by the currently-stored baseline setting.