Cirrus Logic Inc.

Ross Crawford Morgan

Jonathan Taylor

Tahir Rashid

Eric Jerome King

Lingli Zhang

Robert David Rand

Thomas H Hoff

Yongjie Cheng

Michael Robinson

Richard Colin Fitzgerald

John L Melanson

Axel Thomsen

Emmanuel A Marchais

Roberto Napoli

Holger Haiplik

Ivan Perry

Itisha Tyagi

Malcolm Blyth

Angus Black

Kemal S Demirci

Joe Walker

Shantanu Shrikant Nalage

This application relates to methods and apparatus for voltage monitoring of switching drivers. A modulator is configured to receive a modulator input signal and to controlling switching of an output stage of the switching driver to generate a first drive signal. A voltage monitor is configured to receive a first digital signal tapped from the modulator and to generate an indication of output voltage of the first drive signal from the first digital signal by controllably applying an adjustment from the first digital signal to compensate for inaccuracy between the first digital signal and the output voltage. The adjustment is based on monitored operation of the modulator. In some cases the monitored operation may be clipping of the switching driver. In some cases the monitored operation may be a signal generated by the modulator that include a contribution from a feedback signal of output voltage.

Voltage monitoring of switching drivers

An integrated circuit (IC), comprising: a first transducer driver for driving a first transducer; a second transducer driver for driving a second transducer; and boost circuitry comprising first and second boost nodes, the boost converter configurable to boost a supply voltage received at one or more input pins of the IC to provide first and second boosted voltages to respective first and second transducer drivers via respective first and second boost nodes.

Integrated circuits for driving transducers

This application relates to methods and apparatus for clipping prevention. A driver apparatus for driving a transducer has a switching driver configured to switch at least one output node between different switching voltages with a controlled duty-cycle to drive an output signal across the transducer. A clipping prevention controller is configured to control a gain applied to the input signal so as to provide limiting of the input signal to avoid clipping of the output signal. The clipping prevention controller is configured to dynamically control at least one limiting threshold used to determine when to apply limiting of the input signal based on an indication of load resistance of the transducer and the input voltage to the switching driver.

Clipping prevention in switched mode drivers

The present disclosure relates to circuitry comprising: digital circuitry configured to generate a digital output signal; and monitoring circuitry configured to monitor a supply voltage to the digital circuitry and to output a control signal for controlling operation of the digital circuitry, wherein the control signal is based on the supply voltage.

Driver circuitry

A system includes a wireless transmission module configured to transmit electrical energy to a wireless receiver module via reverse wireless charging, one or more electronic components other than the wireless transmission module, a battery configured to provide electrical energy to the wireless transmission module and the one or more electronic components, and a battery management module coupled to the battery and the wireless transmission module. The battery management module is configured to determine an amount of power demanded by the wireless transmission module and the one or more electronic components from the battery and dynamically vary power transfer from the wireless transmission module to the wireless receiver module as a function of the amount of power demanded by the one or more electronic components.

Reverse wireless charging power management

This application relates to methods and apparatus for driving a transducer connected between two output nodes in a bridge-tied-load configuration. A driver receives first and second supply voltages and has charge pumps that generate respective first and second boosted voltages. The driver is operable in a first driver mode in which each output node is modulated between the first and second supply voltage; a second driver mode in which one output nodes is modulated between the first and second supply voltages and the other output node is modulated between either the first boosted voltage and the first supply voltage or between the second supply voltage and the second boosted voltage; and a third driver mode in which one of the output nodes is modulated between the first supply voltage and the first boosted voltage and the other output node is modulated between the second supply voltage and the second boosted voltage.

Driver circuitry and operation

This application relates to methods and apparatus for multichannel drivers for driving transducers in different channels. A multichannel driver has a plurality of output stages configured such that two output nodes can be modulated between selected switching voltages with a controlled duty cycle to generate a differential output signal across a respective transducer, each output stage being operable with different switching voltages in different modes of operation. A first set of two or more of the output stages are arranged to receive a voltage output by a capacitive voltage generator to use as a switching voltage. A controller is configured to control the mode of operation and duty-cycle of each of the output stages based on a respective input signal and also based on operation of the other output stages of the first set.

Multichannel driver circuitry and operation

This application relates to methods and apparatus for driving a transducer with switching drivers. A switching driver has first and second supply node for receiving supply voltages and includes an output bridge stage, a capacitor and a network of switches. The network of switches is operable in different switch states to provide different switching voltages to the output bridge stage. A controller is configured to control the switch state of the network of switches and a duty cycle of output switches of the output bridge stage based on an input signal to generate an output signal for driving the transducer.

A power delivery system may include an inductive power converter comprising a shared connection to a shared voltage from a battery, multiple inductive phases, each of the multiple inductive phases configured to generate a respective voltage from the shared voltage, multiple regulated voltage connections, and one or more switches configured and arranged to selectively assign at least one of the multiple inductive phases to a regulated voltage connection selected from the multiple regulated voltage connections.

Multi-output multi-phase boost converter with dynamically assignable phases

The present disclosure relates to circuitry comprising: pulse-width modulation (PWM) circuitry configured to generate a PWM output signal; and monitoring circuitry configured to monitor a supply voltage to the PWM circuitry and to output a control signal for controlling operation of the PWM circuitry, wherein the control signal is based on the supply voltage.

PWM circuitry

There is provided an apparatus for providing an output signal to an audio transducer, comprising: a first signal path for receiving a first digital audio input signal, applying a first digital gain, and outputting an amplified first digital audio input signal; a second signal path, for receiving a second digital audio input signal, applying a second digital gain, and outputting an amplified second digital audio input signal; converter circuitry, coupled to the first and second signal paths, for converting at least the amplified first and second digital audio input signals into the analogue domain, and outputting an analogue audio input signal; and an analogue gain element, for applying an analogue gain to the analogue audio input signal and outputting the output signal. The apparatus further comprises a control circuit, coupled to the first and second signal paths, operative to select the analogue gain based on a combination of at least the first and second digital audio input signals or signals derived therefrom, and to select the first and second digital gains so as to compensate for the analogue gain.

Systems, apparatus and methods for dynamic range enhancement of audio signals

Clock-controlled circuitry organised into at least first and second clock domains, the first clock domain configured to operate based on a first clock signal and the second clock domain configured to operate based on a second clock signal, wherein: the first clock domain comprises a first signal generator operable to generate a first repetitive signal synchronised to the first clock signal; the second clock domain comprises a second signal generator operable to generate a second repetitive signal synchronised to the second clock signal; the first signal generator is operable, when operating in master mode, to output to the second signal generator a first synchronisation signal indicative of a phase of the first repetitive signal; and the second signal generator is operable, when operating in slave mode, to: set a timing of the second repetitive signal relative to the second clock signal based on the first synchronisation signal so that the second repetitive signal is set to have a phase relationship with the first repetitive signal which then meets a slave specification; and re-set the timing of the second repetitive signal relative to the second clock signal if it is determined that the phase relationship has changed such that it no longer meets the slave specification.

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Edinburgh, United Kingdom

Ross Crawford Morgan