A radio-frequency (RF) amplifier having a direct response to an arbitrary signal source to output one or more electrosurgical waveforms within an energy activation request, is disclosed. The RF amplifier includes a phase compensator coupled to an RF arbitrary source, the phase compensator configured to generate a reference signal as a function of an arbitrary RF signal from the RF arbitrary source and a phase control signal; at least one error correction amplifier coupled to the phase compensator, the at least one error correction amplifier configured to output a control signal at least as a function of the reference signal; and at least one power component coupled to the at least one error correction amplifier and to a high voltage power source configured to supply high voltage direct current thereto, the at least one power component configured to operate in response to the control signal to generate at least one component of the at least one electrosurgical waveform.

An amplifier circuit and a buffer amplifier are provided. The amplifier circuit includes an operational amplifier stage, an output stage, a first compensation capacitor, and a first decoupling circuit. The operational amplifier stage is coupled between a first input terminal, a second input terminal, a first control node, and a second control node. The first compensation capacitor is coupled between the output terminal and the first control node. The first decoupling circuit has a first switch, a first current source and a first ground terminal. The first switch is coupled to the first control node, and the first current source is connected between the first switch and the first ground terminal. The decoupling circuit is used for providing a discharging path for the first coupling current of the first compensation capacitor.

An amplifier includes an output stage circuit and a compensation circuit. The output stage circuit includes a first input terminal, a second input terminal, a first output terminal, and a second output terminal. The compensation circuit includes a first capacitor, a second capacitor, a third capacitor, and a fourth capacitor. The first capacitor is coupled between the first input terminal and the second output terminal, and is configured to operate as a first Miller capacitor. The second capacitor is coupled between the second input terminal and the first output terminal, and is configured to operate as a second Miller capacitor. The third capacitor and the fourth capacitor are configured to alternately operate as the first Miller capacitor and the second Miller capacitor according to at least one clock signal.

In accordance with an embodiment, a circuit includes: a first super source follower; a compensation circuit having a compensating node configured to provide a voltage of opposite phase of a voltage of an internal node of the first super source follower; and a first compensation capacitor coupled between an input of the first super source follower and the compensating node of the compensation circuit.

Embodiments of an amplifiers and integrated circuits include a first transistor and a second transistor. A second current-carrying terminal of the first transistor may be coupled to a first current-carrying terminal of the second transistor and the control terminal of the second transistor may be coupled to a low impedance alternating current (AC) potential node. A bias network that includes a first circuit element and a second circuit element couples the second current-carrying terminal of the second transistor to the control terminal of the second transistor. The first circuit element may be configured to apply a portion of a potential at the second current-carrying terminal of the second transistor to the control terminal of the second transistor, and the second circuit element may be coupled between the control terminal of the second transistor and a fixed potential.

An amplifier that amplifies a differential signal includes first and second input terminals for receiving two input signals; first and second diodes each including an anode and a cathode, the anodes being electrically connected to the first and second input terminals; first and second bias current sources being respectively electrically connected to the cathodes of the first and second diodes; an operational amplifier connected to the cathode of the first diode and the cathode of the second diode and configured to amplify a differential signal between signals generated at the cathodes of the first and second diodes; a capacitive element being electrically connected between an input and an output of the operational amplifier; and a differential amplifier provided between the operational amplifier and the first and second input terminals and configured to amplify the two input signals. The first and second bias current sources include a current mirror circuit.

An embodiment amplifier circuit includes a pair of subcircuits that includes a first subcircuit and a second subcircuit, each of which includes a buffer amplifier and a feedback circuit that includes a feedback capacitor. The amplifier circuit also includes a pair of output terminals. The first subcircuit and the second subcircuit each generate a different output signal of a pair of output signals that includes a first output signal and a second output signal. The amplifier circuit is configured for receiving a positive differential input signal at the first subcircuit, receiving a negative differential input signal at the second subcircuit, and receiving the pair of output signals at the pair of output terminals. The amplifier circuit is also configured for transmitting the first output signal to the feedback circuit of the first subcircuit, and transmitting the second output signal to the feedback circuit of the second subcircuit.

There is described herein methods and devices for high DC gain closed loop operation amplifiers exploiting cascaded low gain stages and a controller-based compensation circuit for stability.

An amplifier arrangement has an input transistor being connected between reference potential terminals by a current source and a current sink. An amplifier stage has an amplifier output coupled to a first connection node between the current sink and a first terminal of the input transistor by means of a feedback path, and an amplifier input connected to a second connection node between the current source and the second terminal of the input transistor. A level-shifting structure has a level-shifting element with one end connected to a reference connection, wherein the level-shifting element is adapted to perform a level-shifting of a potential at the second connection node with respect to a potential at the reference connection. The reference connection is coupled to one of the following: the amplifier output, the first connection node, a control terminal of the input transistor.

There is disclosed a communication cable module including: a conductive cable; a linear amplifier connected to the conductive cable; a detector for detecting presence or absence of an input signal of the conductive cable; a first circuit having a variable-current function; and a second circuit having a common-mode voltage regulating function, wherein when the input signal is not present, the variable-current function of the first circuit reduces an output current of the linear amplifier and the common-mode voltage regulating function of the second circuit regulates an output common-mode voltage of the linear amplifier.