Abstract: The present disclosure relates to circuitry comprising audio amplifier circuitry for receiving an audio signal to be amplified; and first and second output nodes for outputting first and second differential output signals. The circuitry further comprises common mode buffer circuitry configured to receive a common mode voltage and to selectively output the common mode voltage to the first and second output nodes.

Abstract: The present disclosure relates to circuitry comprising audio amplifier circuitry for receiving an audio signal to be amplified; and first and second output nodes for outputting first and second differential output signals. The circuitry further comprises common mode buffer circuitry configured to receive a common mode voltage and to selectively output the common mode voltage to the first and second output nodes.

Abstract: This application relates to methods and apparatus for sensing current in a monitored current path, where the monitored current path is bidirectional such that current can flow in either direction along the monitored current path. A current sensor has first and second sense resistors (401a, 401b) configured to each pass a current corresponding to the current in the monitored current path. The first and second sense resistors are configured to have a matching arrangement, such that current flow through the first sense resistor when current is flowing in one direction in the monitored current path matches current flow through the second sense resistor when current is flowing in the opposite direction in the monitored current path.

Abstract: The present disclosure relates to circuitry for detecting connection of a plug of an audio accessory device to a socket of an intermediate cable that is connected to a host device, wherein the plug of the accessory device is of a different type than the socket of the intermediate cable. The circuitry comprises a monitoring unit comprising a first terminal configured to be electrically connected to a first socket contact of the socket that is in electrical contact with a first plug contact of the plug when the plug is fully received in the socket; and a second terminal configured to be electrically connected to a second socket contact of the socket that is in electrical contact with a second plug contact of the plug when the plug is fully received in the socket.

Abstract: The present invention relates to circuitry comprising: interpolation filter circuitry configured to receive a digital input signal and to output an interpolated digital signal; amplifier circuitry configured to generate an output signal based on the interpolated digital signal; and protection circuitry. The protection circuitry is configured to activate in response to detection of a fault condition at an output of the amplifier circuitry. The circuitry further comprises first detection circuitry configured to output a control signal to disable the protection circuitry on detection of a transient signal at an output of the interpolation filter circuitry that is unrelated to a fault.

Abstract: The present disclosure relates to power converter circuitry, and in particular to power converter circuitry for providing a supply voltage to a load such as amplifier circuitry. In one aspect the invention provides a system comprising: amplifier circuitry; and power converter circuitry for receiving a supply voltage and providing an output voltage to the amplifier circuitry, the power converter circuitry comprising: a control loop for regulating an output voltage of the power converter circuitry in accordance with a target output voltage value; and controller circuitry configured to adjust the target output voltage value if the supply voltage to the power converter circuitry is within a first predefined threshold of a requested output voltage of the power converter circuitry.

Abstract: An integrated circuit (IC), comprising: a converter comprising: one or more core devices; and one or more output internal nodes, each internal node coupled to one of the one or more core devices; protection circuitry comprising: one or more isolation switches, each of the one or more isolation switches coupled between a respective one of the one or more internal output nodes and a respective output external pin of the IC, wherein the protection circuitry configured to: monitor a characteristic at each respective external output pin of the IC; and if the characteristic is outside an operating specification of the one or more core devices, open one or more of the one or more isolation switches to isolate one or more of the one or more core devices from the respective external pin of the IC.

Abstract: Circuitry for estimating an inductance of an inductor in power converter circuitry, the circuitry comprising: circuitry for generating a peak inductor current signal indicative of a peak inductor current during an operational cycle of the power converter circuitry; circuitry for generating a ripple current estimate signal, indicative of an estimate of a ripple current in the power converter circuitry; and circuitry for applying the ripple current estimate signal to the peak inductor current signal to generate an average inductor current threshold signal indicative of an estimated average inductor current in the power converter circuitry during the operational cycle, wherein the ripple current estimate signal is based on: a duration of a charging phase of operation of the power converter circuitry; a voltage across the inductor; and an inductance value for the inductor; and wherein the circuitry for generating the ripple current estimate signal is operative to select an inductance value for the inductor for wh

Abstract: The present disclosure relates to circuitry for selecting a bias voltage to output at a bias voltage output node of the circuitry. The circuitry comprises a first circuit node configured to receive a first voltage from a first, unregulated, voltage source and a second circuit node configured to receive a second voltage from a second, regulated, voltage source. A switch arrangement configured to selectively couple the bias voltage output node to the first circuit node or the second circuit node is also provided.

Abstract: The present invention relates to circuitry comprising: interpolation filter circuitry configured to receive a digital input signal and to output an interpolated digital signal; amplifier circuitry configured to generate an output signal based on the interpolated digital signal; and protection circuitry. The protection circuitry is configured to activate in response to detection of a fault condition at an output of the amplifier circuitry. The circuitry further comprises first detection circuitry configured to output a control signal to disable the protection circuitry on detection of a transient signal at an output of the interpolation filter circuitry that is unrelated to a fault.

Abstract: The present disclosure relates to circuitry for providing an output voltage. The circuitry comprises: voltage generator circuitry configured to provide an output voltage to an output node of the circuitry; current limiter circuitry operable to perform current limiting so as to limit a current supplied at the output node of the circuitry; detection circuitry configured to output a detection signal when a load voltage across a load coupled to the output node of the circuitry reaches a target voltage; and delay circuitry configured to receive the detection signal and to output a control signal to deactivate current limiting by the current limiter circuitry after a predetermined delay period after receiving the detection signal.

Abstract: The present disclosure relates to circuitry comprising audio amplifier circuitry for receiving an audio signal to be amplified; and first and second output nodes for outputting first and second differential output signals. The circuitry further comprises common mode buffer circuitry configured to receive a common mode voltage and to selectively output the common mode voltage to the first and second output nodes.

Abstract: The present disclosure relates to circuitry for selecting a bias voltage to output at a bias voltage output node of the circuitry. The circuitry comprises a first circuit node configured to receive a first voltage from a first, unregulated, voltage source and a second circuit node configured to receive a second voltage from a second, regulated, voltage source. A switch arrangement configured to selectively couple the bias voltage output node to the first circuit node or the second circuit node is also provided.

Abstract: The present disclosure relates to circuitry for detecting connection of a plug of an audio accessory device to a socket of an intermediate cable that is connected to a host device, wherein the plug of the accessory device is of a different type than the socket of the intermediate cable. The circuitry comprises a monitoring unit comprising a first terminal configured to be electrically connected to a first socket contact of the socket that is in electrical contact with a first plug contact of the plug when the plug is fully received in the socket; and a second terminal configured to be electrically connected to a second socket contact of the socket that is in electrical contact with a second plug contact of the plug when the plug is fully received in the socket.