A method may include processing a first signal derived from an input signal with a first path to generate a first path voltage at a first path output, processing a second signal derived from the input signal with a second path to generate a second path voltage at a second path output, the second path comprising a linear amplifier having at least one transistor for driving the second path voltage, generating the first signal and the second signal with a signal splitter, such that the second signal comprises information of the input signal absent from the first signal, and such that the second path voltage is of a sufficient magnitude such that the at least one transistor operates in a saturation region of the at least one transistor throughout a dynamic range of a load voltage equal to the difference of the first path voltage and the second path voltage.

A method may include processing a first signal derived from an input signal with a first path to generate a first path voltage at a first path output, processing a second signal derived from the input signal with a second path to generate a second path voltage at a second path output, the second path comprising a linear amplifier having at least one transistor for driving the second path voltage, generating the first signal and the second signal with a signal splitter, such that the second signal comprises information of the input signal absent from the first signal, and such that the second path voltage is of a sufficient magnitude such that the at least one transistor operates in a saturation region of the at least one transistor throughout a dynamic range of a load voltage equal to the difference of the first path voltage and the second path voltage.

An audio output circuit drives an electroacoustic conversion element. A Class D amplifier has a segmented configuration including multiple segments arranged in parallel. A pulse modulator pulse modulates an audio signal. A level detector detects the amplitude of the audio signal. A driver selectively drives the multiple segments of the Class D amplifier according to the output of the level detector.

An audio output circuit drives an electroacoustic conversion element. A Class D amplifier has a segmented configuration including multiple segments arranged in parallel. A pulse modulator pulse modulates an audio signal. A level detector detects the amplitude of the audio signal. A driver selectively drives the multiple segments of the Class D amplifier according to the output of the level detector.

Various implementations include systems for amplifying input signals. In particular implementations, a system includes a common mode voltage controller configured to receive an input signal and output a pair of adjusted signals; a modulator that generates a pair of pulse width modulation (PWM) signals in response to the adjusted signals; and a self-boosting push pull amplifier configured to receive the PWM signals and generate an amplified output, wherein the self-boosting push pull amplifier is configured to generate a differential mode voltage representative of an amplified version of the input signal, wherein the adjusted audio signals generated by the common mode voltage controller include a dynamically adjusted gain and duty cycle offset that causes the self-boosting push pull amplifier to operate with a reduced common mode voltage.

A Class D amplifier comprising a control circuit configured to receive an audio input signal and derive first, second and third PWM switching control signals therefrom, being supplied to respectively first, second and third switches of a driver, the first and second switches being serially arranged between first and second supply voltages, and having a common node coupled to an output terminal. The driver comprises a DC level shifter being configured to provide a reference voltage to a reference terminal in at least first and second states of operation, said reference voltage including a DC component at least substantially equidistant between the first and second supply voltages. Said third switch being included in a shunt path between the output and the reference terminal.

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.

A novel phantom-powered inline preamplifier is configured to provide selective processing of a sound source signal by intelligently determining the need for a low or high impedance matching and transformer coupling, based on high fidelity requirements of a particular sound source signal. For example, the phantom-powered inline preamplifier can intelligently detect a microphone-originating sound source signal and automatically route the microphone-originating sound source signal to a low impedance matching circuit pathway that leads to a phantom-powered output terminal for an optimal hi-fidelity processing specific to the microphone-originating sound source signal. Likewise, the phantom-powered inline preamplifier can intelligently detect a musical instrument-originating sound source signal and automatically route the musical instrument-originating sound source signal to a high impedance matching circuit pathway and optionally couple to an instrument transformer, which leads to the phantom-powered output terminal for an optimal hi-fidelity processing specific to the musical instrument-originating sound source signal.

An amplifier circuit with in-band gain degradation compensation is shown. The amplifier circuit has an input-stage amplifier, at least one intermediate-stage amplifier, and an output-stage amplifier cascaded between an input port and an output port of the amplifier circuit. A compensation capacitor is coupled between the output port of the amplifier circuit and an output port of the input-stage amplifier. A high-order damping circuit is coupled to an output port of the intermediate-stage amplifier.

Systems and methods include a circuit having a plurality of integrator circuits arranged in series and configured to receive an input signal at a first of the plurality of integrators and generate an output signal at a last of the plurality of integrators, a filter arranged to receive a feedback signal comprising the output signal and generate a filtered feedback signal, which is applied to the input signal before input to the first of the plurality of integrators, and a feedback signal path configured to receive the feedback signal and apply the feedback signal to an input of a second of the plurality of integrators. The circuit may include a class-D amplifier and/or a delta-sigma modulator. The input signal may include an analog audio signal that is amplifier to drive an audio speaker.