An output driver with programmable single-ended and differential outputs includes a first switch, a first output attenuator, and a programmable attenuator. The first switch is coupled in a shunt configuration to a first path of a differential output of a first amplifier. The first output attenuator is included in the first path and is coupled to the first switch in accordance with the shunt configuration. The programmable attenuator is included in a second path of the differential output of the first amplifier.

A two-stage circuit includes a differential-to-single-ended first stage with a differential pair of transistors. The first stage includes a current mirror including a diode-connected transistor having an RC circuit coupled to a drain of the diode-connected transistor. The current mirror is configured to mirror a power supply noise current conducted by the RC circuit through a first stage output terminal to a gate of an output transistor in a second stage of the two-stage circuit.

An apparatus includes an input amplifier stage and a switch that has a first terminal at a virtual ground input of the input amplifier stage.

An audio amplifier, including: at least a two stage amplifier configured to receive an input signal and output an amplified output signal, the at least a two stage amplifier including at least one stage amplifier and an output stage amplifier; and an auxiliary stage amplifier having an input coupled to an output of the at least one stage amplifier and an input of the output stage amplifier.

A parallel resonant circuit with excellent distortion and saturation characteristics is provided at low power consumption. A first power-supply voltage is applied to the parallel resonant circuit. In the parallel resonant circuit, a variable resistor includes one or more parallel-connected branches. Each of the branches includes a series circuit of a resistor and a MOS switch. A second power supply supplies power of control signals applied to respective gates of the MOS switches, and supplies back gate voltages to the MOS switches. A power-supply voltage of the second power supply is higher than the first power-supply voltage.

An apparatus includes an input amplifier stage and a switch that has a first terminal at a virtual ground input of the input amplifier stage.

The invention relates to a high-performance audio amplifier intended to control at least one loudspeaker, the amplifier comprising a pre-amplification stage that receives an input signal, a power amplification stage connected to the pre-amplification stage and a feedback that delivers to the pre-amplification stage an image of the output signal, the power amplification stage comprising two power supply circuits comprising a MOSFET transistor. The invention is characterized in that it comprises: a sub-circuit for assisting with charging, a sub-circuit for assisting with discharging said MOSFET transistor, and a voltage-shifting sub-circuit.

The invention relates to a high-performance audio amplifier intended to control at least one loudspeaker, the amplifier comprising a pre-amplification stage that receives an input signal, a power amplification stage connected to the pre-amplification stage and a feedback that delivers to the pre-amplification stage an image of the output signal, the power amplification stage comprising two power supply circuits comprising a MOSFET transistor. The invention is characterized in that it comprises: a sub-circuit for assisting with charging, a sub-circuit for assisting with discharging said MOSFET transistor, and a voltage-shifting sub-circuit.