A differential-follower control circuit has been provided, comprising: a follower; an output-voltage following module, which controls a voltage at a control terminal of the follower to vary with an output voltage; a substrate-voltage following module, which controls a substrate voltage of an output transistor of the follower to vary with an input voltage; an output terminal of the follower is connected to a first terminal of the output-voltage following module; a second terminal of the output-voltage following module is connected to the control terminal of the follower; a first terminal of the substrate-voltage following module is connected to an input terminal of the follower and a second terminal of the substrate-voltage following module is connected to a substrate of the output transistor; the invention effectively improves the overall linearity of the follower.

Disclosed herein is a method including sinking current from a pair of input transistors of a differential amplifier while sourcing more current to the pair of input transistors than is sunk. The method further includes generating a pair of input differential signals using a pair of input voltage regulators, and amplifying a difference between the pair of input differential signals to produce a pair of differential output voltages, using the differential amplifier. The method also includes amplifying the pair of differential output voltages using at least one voltage gain amplifier, and generating control signals for current sources that source the current to the pair of input transistors of the differential amplifier, from the pair of differential output voltages after at least amplification.

Disclosed herein is a method including sinking current from a pair of input transistors of a differential amplifier while sourcing more current to the pair of input transistors than is sunk. The method further includes generating a pair of input differential signals using a pair of input voltage regulators, and amplifying a difference between the pair of input differential signals to produce a pair of differential output voltages, using the differential amplifier. The method also includes amplifying the pair of differential output voltages using at least one voltage gain amplifier, and generating control signals for current sources that source the current to the pair of input transistors of the differential amplifier, from the pair of differential output voltages after at least amplification.

Disclosed herein is a circuit including a differential amplifier having a pair of input transistors coupled in a differential arrangement between adjustable current sources and receiving input differential signals from a pair of input voltage regulators. The adjustable current sources are configured to source more current to the pair of input transistors than current that is sunk from the pair of input transistors. A first amplifier has inputs coupled to receive differential output voltages from the differential amplifier. A second amplifier has inputs coupled to receive amplified differential output voltages from the first amplifier. A low pass filter has inputs coupled to receive further amplified differential output voltages from the second amplifier and produce final differential output voltages.

A buffer amplifier comprises a source follower and a feedback amplifier. The feedback amplifier may be configured to control a drain current of the source follower to remain substantially constant independent of a load.

A buffer amplifier comprises a source follower and a feedback amplifier. The feedback amplifier may be configured to control a drain current of the source follower to remain substantially constant independent of a load.

In an output amplifier stage of an operational amplifier circuit, the first p-well of the first nMOSFET and the second p-well of the second nMOSFET are connected to the fourth node. Further, the first n-well of the first pMOSFET and the second n-well of the second pMOSFET are connected to the fifth node. At least one of the fourth node and the fifth node is connected to an output terminal VOUT.

Independent control loops for mitigating positive and negative mismatch in differential amplifiers are provided. A method includes comparing a first voltage measured at a positive side output of an emitter follower with a reference voltage, resulting in a first voltage difference. The method also includes comparing a second voltage measured at a negative-side output of the emitter follower with the reference voltage, resulting in a second voltage difference. In addition, the method includes independently controlling the positive side and the negative side of the differential amplifier based on the first voltage difference and the second voltage difference.

In an output amplifier stage of an operational amplifier circuit, the first p-well of the first nMOSFET and the second p-well of the second nMOSFET are connected to the fourth node. Further, the first n-well of the first pMOSFET and the second n-well of the second pMOSFET are connected to the fifth node. At least one of the fourth node and the fifth node is connected to an output terminal VOUT.

A differential-follower control circuit has been provided, comprising: a follower; an output-voltage following module, which controls a voltage at a control terminal of the follower to vary with an output voltage; a substrate-voltage following module, which controls a substrate voltage of an output transistor of the follower to vary with an input voltage; an output terminal of the follower is connected to a first terminal of the output-voltage following module; a second terminal of the output-voltage following module is connected to the control terminal of the follower; a first terminal of the substrate-voltage following module is connected to an input terminal of the follower and a second terminal of the substrate-voltage following module is connected to a substrate of the output transistor; the invention effectively improves the overall linearity of the follower.