Abstract: Embodiments described herein provide an audio device and a method of operating the audio device. The audio device comprises at least one surface, a first surface transducer positioned to excite first modes of oscillation in a first surface of the at least one surface, and a second surface transducer positioned to excite second modes of oscillation in a second surface of the at least one surface, wherein the first modes of oscillation are of a higher frequency than the second modes of oscillation.

Abstract: The application relates to a MEMS transducer package comprising: a package substrate the package substrate comprising a substrate channel, the substrate channel comprising first and second channel portions, wherein the first portion extends in a first direction between a first channel opening in a side surface of the substrate and a junction between the first and second channel portions, and wherein the second portion extends in a second direction between said junction and a second channel opening at, or underlying, a substrate opening provided in an upper surface of the package substrate.

Abstract: This application relates to time-encoding modulators (TEMs). A TEM (100) receives an input signal (SIN) and outputs a time encoded signal (SPWM). A comparator (101) is located within a forward signal path of a feedback loop of the TEM. Also in the feedback loop are a filter (104) and a delay element (106) for applying a controlled delay. In some embodiments a latching element (101, 302; 106, 402) is located within the forward signal path to synchronise any signal transitions output from the latching element to a received first clock signal. Any signal transitions in the output (SOUT) from the modulator are thus synchronised to the first clock signal. In some embodiments the delay element (106) is a digital delay element which is synchronised to the first clock signal.

Abstract: A method, comprising: obtaining one or more accelerometer signals derived from an accelerometer; and determining one or more parameters of wind at the accelerometer based on the one or more accelerometer signals.

Abstract: A method may include operating a DC-DC switch converter in a forced continuous conduction mode in which for each switching cycle of the switch converter during the forced continuous conduction mode, the switch converter operates in a series of phases including: a first phase in which an inductor current flowing in an inductor of the switch converter increases from zero to a controlled positive current magnitude with respect to a first terminal and a second terminal of the inductor; a second phase in which the inductor current decreases from the controlled positive current magnitude to approximately zero; a third phase in which the inductor current decreases from approximately zero to a controlled negative current magnitude with respect to a first terminal and a second terminal of the inductor; and a fourth phase in which the inductor current increases from the controlled negative current magnitude to approximately zero.

Abstract: A Class-D amplifier includes a plurality of power rails, a quantizer, and a driver stage. The quantizer and the driver stage have a combined gain. For each power rail of the plurality of power rails, the Class-D amplifier senses a voltage value for the power rail and determines a ramp amplitude based on the sensed voltage value. The Class-D amplifier concurrently switches from the driver stage using a first power rail to a second power rail of the plurality of power rails and switches from the quantizer using the ramp amplitude associated with the first power rail to using the ramp amplitude associated with the second power rail so that the combined gain is constant.

Abstract: A temperature sensor having a two-state input current, an element whose temperature is sensed based on a change in voltage across the element induced by the two states of the input current, a charge-to-digital converter, and a capacitor continuously connected between the element and the charge-to-digital converter. The capacitor experiences a charge difference due to the change in voltage across the element induced by the two states of the input current, and the charge-to-digital converter converts the charge difference to a digital value indicative of the temperature of the element. A two-state DC-shifting current having opposite polarity of the two-state input current, a pull-down resistor whose voltage varies with the two-states of the DC-shifting current, and a second capacitor continuously connected between the pull-down resistor and the charge-to-digital converter operate to shift down a DC operating point of the charge-to-voltage converter to increase its dynamic range.

Abstract: Described embodiments generally relate to a signal processing device for on ear detection for an earbud. The device comprises a first microphone input for receiving a microphone signal from a first microphone, the first microphone being configured to be positioned within an ear of a user when the earbud is being worn; a second microphone input for receiving a microphone signal from a second microphone, the second microphone being configured to be positioned outside the ear of the user when the earbud is being worn; a signal generator configured to generate a signal for acoustic playback from a speaker configured to be positioned within the earbud; and a processor.

Abstract: An open-loop digital-to-analog converter (DAC) circuit may include a delta-sigma modulator, a decode block responsive to the delta-sigma modulator configured to perform a DAC decode operation, a plurality of DAC elements responsive to the DAC decode operation, an analog output driver responsive to the plurality of DAC elements, a test signal generator configured to generate a test signal that is responsive to inputs of the plurality of DAC elements, and a synchronizer configured to enable replication of the test signal at an external test system coupled to the open-loop DAC circuit in order to generate a matching test signal at the external test system that matches the test signal generated by the test signal generator.

Abstract: A method may include monitoring an input power supply, monitoring an inductance of an inductor of a boost converter, monitoring one or more other characteristics of the boost converter, and calculating a target peak inductor current based on the input power supply voltage, the inductance, the one or more other characteristics of the boost converter, and a target average current of the inductor during a switching cycle of the boost converter. A method may include monitoring an input power supply voltage, monitoring an inductance of an inductor of a boost converter, monitoring one or more other characteristics of the boost converter, and calculating an average current of the inductor during a switching cycle of the boost converter based on the input power supply voltage, the inductance, the one or more other characteristics of the boost converter, and a peak inductor current of the inductor.

Abstract: A system includes a sequencer that divides a reference waveform into reference sequences, a sequence adjuster, and a model that models non-linearities of a haptic rendering signal chain that includes a haptic transducer load and a driver to the load. For each reference sequence: the sequence adjuster transforms the reference sequence into a test sequence using one or more parameters (e.g., changes reference sequence amplitude and/or period), the model generates an output in response to the test sequence, an error signal is generated that measures a difference between the output and the reference sequence, and if the error signal is above a threshold the parameters are adjusted based on the error signal. These operations are repeated until the error signal is below the threshold in which case the test sequence becomes a selected sequence, which is then sent to the haptic rendering signal chain.

Abstract: The application describes method and apparatus for amplification. An amplifier circuit (300) is described for driving a load (101) connected between first and second output nodes (103p, 103n) based on an input signal (Sin). The amplifier circuit includes first and second signal paths for generating respective first and second driving signals (Soutp and Soutn) at the first and second output nodes, each of the first and second signal paths comprising a respective sigma-delta modulator (301p, 301n). A correlation controller (302) is configured to control the first and second signal paths to provide correlation between at least some noise components of the first and second driving signals.

Abstract: This application describes an amplifier circuit (200) with a forward signal path with a class-D output stage (102) for generating a driving signal (Sout) based on a digital input signal (Sin). The amplifier has a first feedback path for providing a first digital feedback signal (Sfb1) based on the driving signal and a second feedback path for providing a second digital feedback signal (Sfb2) from a digital part of the forward signal path. The digital input signal (Sin) is combined with a selected feedback signal (Sfbs). The amplifier circuit is selectively operable in a first mode, in which the first feedback signal is used as the selected feedback signal, and in a second mode, in which the second feedback signal is used as the selected feedback signal. A calibration module (204) is operable to calibrate the first feedback path to reduce any DC offset when the amplifier circuit is operating in the second mode.

Abstract: A method for controlling one or more parameters of an amplifier system may include receiving an indication of a physical quantity associated with the amplifier system, determining one or more parameters of the amplifier system in response to the indication, and causing the amplifier system to operate in accordance with the one or more parameters.

Abstract: Embodiments described herein provide an audio device and a method of operating the audio device. The audio device comprises at least one surface, a first surface transducer positioned to excite first modes of oscillation in a first surface of the at least one surface, and a second surface transducer positioned to excite second modes of oscillation in a second surface of the at least one surface, wherein the first modes of oscillation are of a higher frequency than the second modes of oscillation.

Abstract: A method of analysis of an audio signal comprises: receiving an audio signal representing speech; extracting first and second components of the audio signal representing first and second acoustic classes of the speech respectively; analysing the first and second components of the audio signal with models of the first and second acoustic classes of the speech of an enrolled user. Based on the analysing, information is obtained information about at least one of a channel and noise affecting the audio signal.

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 cough detection in a headset, the method comprising: receiving a first signal from an external transducer of the headset; receiving a second signal from an in-ear transducer of the headset; and detecting a cough of a user of the headset based on the first and second signals.

Abstract: This application relates to control of semiconductor devices, in particular MOS devices, so as to reduce RTS/flicker noise. A circuit (100) includes a first MOS device (103, 104) and a bias controller (107). The circuit is operable in at least a first circuit state (PRO) in which the first MOS device is active to contribute to a first signal (Sout) and a second circuit state (PRST) in which the first MOS device does not contribute to the first signal. The bias controller is operable to control voltages at one or more terminals of the first MOS device to apply a pre-bias (VRB1, VPB2) during an instance of the second circuit state. The pre-bias is applied to set an occupancy state of charge carriers traps within the first MOS device, to limit noise during subsequent operation in the first circuit state. In embodiments, the bias controller is configured so that at least one parameter of the pre-bias is selectively variable in use based on one or more operating conditions.

Abstract: The present application relates to structures for supporting mechanical, electrical and/or electromechanical components, devices and/or systems and to methods of fabricating such structures. The application describes a primary die comprising an aperture extending through the die. The aperture is suitable for receiving a secondary die. A secondary die may be provided within the aperture of the primary die.