An amplification device comprising: a push pull circuit which amplifies an input signal; a diamond buffer circuit to which the signal which is amplified by the push pull circuit is input; and a current mirror circuit which is connected to a power supply and the diamond buffer circuit and is connected to a retraction current terminal of the push pull circuit.

A signal modulator for modulating at least one input signal is disclosed. The modulator includes an adaptive ramp generator receiving a clock signal having a clock cycle. The adaptive ramp generator provides a ramp signal having a profile starting from a minimum level adjusted in each clock cycle. The signal modulator may receive a first, second, and third input signal, and a clock signal. The first and second input signals may derive from a single signal where the second signal is equal to the first signal shifted by 180 degrees. The third signal may be a fixed level that sets the nominal duty cycle of the modulator. The input signal having the highest amplitude among the first, second, and third input signals is identified. The minimum level of the ramp signal is adjusted, and the peak value of the ramp maintained substantially equal to the signal having the highest amplitude.

A signal modulator for modulating at least one input signal is disclosed. The modulator includes an adaptive ramp generator receiving a clock signal having a clock cycle. The adaptive ramp generator provides a ramp signal having a profile starting from a minimum level adjusted in each clock cycle. The signal modulator may receive a first, second, and third input signal, and a clock signal. The first and second input signals may derive from a single signal where the second signal is equal to the first signal shifted by 180 degrees. The third signal may be a fixed level that sets the nominal duty cycle of the modulator. The input signal having the highest amplitude among the first, second, and third input signals is identified. The minimum level of the ramp signal is adjusted, and the peak value of the ramp maintained substantially equal to the signal having the highest amplitude.

A Class D amplifier having an integrating primary amplifier with an internal feedback, the amplifier further comprising a feedback loop with a filter of at least second order.

A first module is configured to, based on an input sample, determine a first duty cycle. A second module is configured to, based on a battery voltage and the first duty cycle, determine a second duty cycle. A third module is configured to: set a scalar value based on at least one of a battery current, an amplitude of the input sample, the second duty cycle, and an output voltage; and generate a start signal at a rate equal to a predetermined rate multiplied by the scalar value. A fourth module is configured to set a third duty cycle based on the second duty cycle and the scalar value. A fifth module is configured to generate a PWM output based on the start signal and the third duty cycle. A sixth module is configured to apply power to gates of FETs of a voltage converter based on the PWM output.

Certain aspects of the present disclosure are generally directed to circuitry and techniques for adjusting an audio signal to avoid undesirable system behavior under low alternating-current (AC) line voltage and high volume conditions. For example, certain aspects provide an apparatus for audio amplification. The apparatus generally includes an amplifier, a supply voltage generation circuit having an input coupled to an input voltage node of the apparatus and an output coupled to a supply voltage terminal of the amplifier, the supply voltage generation circuit having a transformer, a primary winding of the transformer being coupled to the input voltage node, a peak voltage detector circuit configured to detect a peak voltage at a secondary winding of the transformer, and a controller circuit configured to adjust an input audio signal of the amplifier based on the detected peak voltage.

A regulated high side gate driver circuit for power transistors includes: a gate driver having a high side positive supply voltage port and a high side negative supply voltage port, and a floating voltage regulator. The floating voltage regulator includes: a positive regulator input, connectable to a high side DC voltage supply; a regulated DC voltage output; a negative regulator input; a DC reference voltage generator configured to generate a DC reference voltage; and a regulation capacitor connected between positive and negative terminals of the DC reference voltage generator, and configured to suppress noise and ripple within the generated DC reference voltage. The negative regulator input is connected to the high side negative supply voltage port and the regulated DC voltage output is connected to the high side positive supply voltage port of the gate driver.

Certain aspects of the present disclosure are generally directed to circuitry and techniques for adjusting an audio signal to avoid undesirable system behavior under low alternating-current (AC) line voltage and high volume conditions. For example, certain aspects provide an apparatus for audio amplification. The apparatus generally includes an amplifier, a supply voltage generation circuit having an input coupled to an input voltage node of the apparatus and an output coupled to a supply voltage terminal of the amplifier, the supply voltage generation circuit having a transformer, a primary winding of the transformer being coupled to the input voltage node, a peak voltage detector circuit configured to detect a peak voltage at a secondary winding of the transformer, and a controller circuit configured to adjust an input audio signal of the amplifier based on the detected peak voltage.

Certain aspects of the present disclosure are generally directed to circuitry and techniques for adjusting an audio signal to avoid undesirable system behavior under low alternating-current (AC) line voltage and high volume conditions. For example, certain aspects provide an apparatus for audio amplification. The apparatus generally includes an amplifier, a supply voltage generation circuit having an input coupled to an input voltage node of the apparatus and an output coupled to a supply voltage terminal of the amplifier, the supply voltage generation circuit having a transformer, a primary winding of the transformer being coupled to the input voltage node, a peak voltage detector circuit configured to detect a peak voltage at a secondary winding of the transformer, and a controller circuit configured to adjust an input audio signal of the amplifier based on the detected peak voltage.

An RF signal generation device includes an RF signal generation unit 102 that pulse-modulates a prescribed signal to generate an output signal in which four or more-level discrete output levels appear and that a lowest level and any other level appear alternately; a code converter 91 that converts the output signal from the RF signal generation unit 102 into an RF signal in which a smaller number of levels than the number of levels in the output signal; a driver unit 203 that converts the RF signal from the code converter 91 into a binary signal comprising plural bits in which bits corresponding to signal levels in the RF signal are significant; and a digital amplifier 303 that outputs a voltage corresponding to levels in the RF signal outputted from the code converter 91, on the basis of an output signal from the driver unit 203.