This invention provides compact Power Amplifiers with improved efficiency of the circuitry and improved heat dissipation, together achieved much smaller enclosure size for use in modern installations requiring reduced height such as between the thin flat TV and wall, under the table or on the projector pole or in ceiling box and the like.

This invention provides compact Power Amplifiers with improved efficiency of the circuitry and improved heat dissipation, together achieved much smaller enclosure size for use in modern installations requiring reduced height such as between the thin flat TV and wall, under the table or on the projector pole or in ceiling box and the like.

A supply voltage conditioning circuit comprises a differential amplifier, a comparator, a sample and hold (S/H) circuit, and a delay circuit. The differential amplifier receives an input supply voltage and a reference voltage, and outputs a difference signal. The comparator receives the difference signal and a value representative of a noise margin, and outputs a control signal indicative of whether the difference signal is greater than the value representative of the noise margin. The S/H circuit samples the input supply voltage in response to the control signal indicating the difference signal is greater than the noise margin, and outputs a substantially noise free supply voltage. This allows the output supply voltage to track underlying changes in the input supply voltage but filter out noise in the input supply voltage. The delay circuit receives and delays the output supply voltage to generate the reference voltage.

A supply voltage conditioning circuit comprises a differential amplifier, a comparator, a sample and hold (S/H) circuit, and a delay circuit. The differential amplifier receives an input supply voltage and a reference voltage, and outputs a difference signal. The comparator receives the difference signal and a value representative of a noise margin, and outputs a control signal indicative of whether the difference signal is greater than the value representative of the noise margin. The S/H circuit samples the input supply voltage in response to the control signal indicating the difference signal is greater than the noise margin, and outputs a substantially noise free supply voltage. This allows the output supply voltage to track underlying changes in the input supply voltage but filter out noise in the input supply voltage. The delay circuit receives and delays the output supply voltage to generate the reference voltage.

Various techniques are provided to reduce common mode disturbance associated with an amplifier, such as a class D amplifier. In one example, an amplifier includes a power stage configured to generate first and second PWM signals. The amplifier further includes an integration stage comprising input nodes configured to receive an input differential analog signal. The integration stage is configured to generate an output differential analog signal in response to the PWM signals and the input differential analog signal. The amplifier further includes an active compensation circuit configured to provide a compensation signal to the integration stage to reduce disturbances at the input nodes associated with the PWM signals switching between a common mode and a differential mode. Additional devices, systems, and methods are also provided.

Various techniques are provided to reduce common mode disturbance associated with an amplifier, such as a class D amplifier. In one example, an amplifier includes a power stage configured to generate first and second PWM signals. The amplifier further includes an integration stage comprising input nodes configured to receive an input differential analog signal. The integration stage is configured to generate an output differential analog signal in response to the PWM signals and the input differential analog signal. The amplifier further includes an active compensation circuit configured to provide a compensation signal to the integration stage to reduce disturbances at the input nodes associated with the PWM signals switching between a common mode and a differential mode. Additional devices, systems, and methods are also provided.

Current monitoring techniques are included in an electronic system that provides power to a load from a power output stage that supplies power to a load. Multiple current control devices form the power output stage in series with multiple sense resistors that provide corresponding sense voltages indicative of current provided through the multiple current control devices to the load in the same or different time intervals. A calibration control circuit controls injection of current through the multiple sense resistors individually and measures the corresponding sense voltages generated by the current to determine resistance values of the multiple sense resistors. A correction subsystem computes a first ratio of a first resistance to a second resistance and a second ratio of a third resistance to a fourth resistance of the multiple sense resistors, and controls compensation for a difference between the first ratio and the second ratio to remove the measurement error.

Current monitoring techniques are included in an electronic system that provides power to a load from a power output stage that supplies power to a load. Multiple current control devices form the power output stage in series with multiple sense resistors that provide corresponding sense voltages indicative of current provided through the multiple current control devices to the load in the same or different time intervals. A calibration control circuit controls injection of current through the multiple sense resistors individually and measures the corresponding sense voltages generated by the current to determine resistance values of the multiple sense resistors. A correction subsystem computes a first ratio of a first resistance to a second resistance and a second ratio of a third resistance to a fourth resistance of the multiple sense resistors, and controls compensation for a difference between the first ratio and the second ratio to remove the measurement error.

Systems and methods for protecting a loudspeaker from excessive excursion include an audio source, an adaptive excursion protection filter, an audio clipper, an inverse excursion protection filter, an amplifier and a loudspeaker. The system performs operations including receiving an audio signal, applying an excursion protection filter, the excursion protection filter adapting in real-time to one or more speaker conditions, clipping the audio signal, applying an inverse excursion protection filter, and amplifying, using an amplification circuit, the audio signal for output to the speaker.

A switching amplifier provided, at a minimum, with: a first input transistor into which one of two input signals that operate in a complementary manner is input; a first cascode transistor cascade-connected between the first input transistor and a power supply; a second input transistor into which the other of the two input signals is input; and a second cascode transistor cascade-connected between the second input transistor and the first input transistor; the switching amplifier extracting an output signal, a connection point between the first input transistor and the second cascode transistor being used as an output terminal; wherein a first potential limiting circuit and a second potential limiting circuit for limiting the potential fluctuation range are respectively connected to the input terminal of the first cascode transistor and the input terminal of the second cascode transistor.