A class-D amplifier with multiple “nested” levels of feedback. The class-D amplifier surrounds an inner feedback loop, which takes the output of a switching amplifier and corrects for errors generated across the switching amplifier, with additional feedback loops that also take the output of the switching 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.

A boost class-D amplifier includes a PWM modulator, a boost level controller coupled to the PWM modulator, a pre-driver coupled to the PWM modulator and the boost level controller, a system voltage source, an inductor coupled to the system voltage source, a first switch, a second switch, a third switch, a fourth switch, a first diode coupled between the third switch and a voltage ground, a second diode coupled between the fourth switch and the voltage ground, and a capacitor coupled between the first switch and the fourth switch. The PWM modulator is for receiving an input signal and generating a first modulated signal accordingly. The boost level controller is for receiving the first modulated signal and generating a second modulated signal accordingly. The pre-driver is for receiving the first modulated signal and the second modulated signal and generating control signals accordingly.

An amplifier includes an input circuit configured to receive an analog input signal and a feedback signal, and output an analog error signal based on the analog input signal and the feedback signal. An ADC is configured to convert the analog error signal into a digital signal in a phase domain. A digital control circuit is configured to generate a digital control signal based on the digital signal in the phase domain. An output circuit is configured to generate an amplified output signal based on the digital control signal, and a feedback circuit is configured generate the feedback signal based on the amplified output signal.

A power control system for audio power amplifiers, especially in the automotive segment, dynamically controlling the output voltage through the reading of the input and output currents, and other parameters, automatically adjusting the amplifier to the load and to the operation conditions, allowing that the amplifier always operates within the safe operation range.

A method of regulating power supply to a speaker and a system for regulating power supply to a speaker comprising a generating of a low frequency signal output to the speaker, sensing a current and a voltage of the speaker after the low frequency signal is output to the speaker, measuring an impedance of the speaker based on the current and voltage, determining a temperature of the speaker and comparing with a threshold value, and lowering a power supply to the speaker where the temperature is above the threshold value.

A method of regulating power supply to a speaker and a system for regulating power supply to a speaker comprising a generating of a low frequency signal output to the speaker, sensing a current and a voltage of the speaker after the low frequency signal is output to the speaker, measuring an impedance of the speaker based on the current and voltage, determining a temperature of the speaker and comparing with a threshold value, and lowering a power supply to the speaker where the temperature is above the threshold value.

A power supply includes a first DC-DC converter coupled to receive power from a first power source, a second DC-DC converter coupled to receive power from a second power source, and a control block. The first DC-DC converter is operable to generate a regulated power supply voltage on an output node of the power supply. The first power source has a maximum output current limit. The second DC-DC converter is also operable to generate a regulated power supply voltage on the output node. The control block is designed to generate the regulated power supply voltage based on both of the first DC-DC converter and the second DC-DC converter.

The present disclosure relates to circuitry comprising: amplifier circuitry configured to receive a variable supply voltage, wherein the supply voltage varies according to an output signal of the amplifier circuitry; monitoring circuitry configured to monitor one or more parameters of an output signal of the amplifier circuitry; and processing circuitry configured to receive an indication of the voltage of the variable supply voltage and an indication of the monitored parameters from the monitoring circuitry and to apply a correction to one or more of the monitored parameters to compensate for coupling between the variable supply voltage and the monitoring circuitry.

The present disclosure relates to circuitry comprising: amplifier circuitry configured to receive a variable supply voltage, wherein the supply voltage varies according to an output signal of the amplifier circuitry; monitoring circuitry configured to monitor one or more parameters of an output signal of the amplifier circuitry; and processing circuitry configured to receive an indication of the voltage of the variable supply voltage and an indication of the monitored parameters from the monitoring circuitry and to apply a correction to one or more of the monitored parameters to compensate for coupling between the variable supply voltage and the monitoring circuitry.