Various embodiments of the present technology may comprise methods and apparatus for an amplifier circuit. Methods and apparatus for an amplifier circuit according to various aspects of the present invention may comprise a first cross-connect circuit configured to receive an input signal at an input terminal and transmit the input signal to an input stage circuit. The amplifier circuit may further comprise a second cross-connect circuit connected between the input stage circuit and an output stage circuit, and a voltage adjustment circuit connected to the input stage circuit. Each cross-connect circuit may comprise a plurality of switches.

Disclosed examples include differential amplifier circuits and variable neutralization circuits for providing an adjustable neutralization impedance between an amplifier input node and an amplifier output node, including neutralization impedance T circuits with first and second impedance elements in series between the amplifier input and output, and a third impedance element, including a first terminal connected to a node between the first and second impedance elements, and a second terminal connected to a transistor. The transistor operates according to a control signal to control the neutralization impedance between the amplifier input node and the amplifier output node.

Disclosed examples include differential amplifier circuits and variable neutralization circuits for providing an adjustable neutralization impedance between an amplifier input node and an amplifier output node, including neutralization impedance T circuits with first and second impedance elements in series between the amplifier input and output, and a third impedance element, including a first terminal connected to a node between the first and second impedance elements, and a second terminal connected to a transistor. The transistor operates according to a control signal to control the neutralization impedance between the amplifier input node and the amplifier output node.

An output of a first amplifier is coupled to an input of a first track and hold circuit and an input of a second track and hold circuit. An input of a first summing circuit is also coupled to an output of the first track and hold circuit and an output of the second track and hold circuit. In addition, an input of a second summing circuit is coupled to the output of the first track and hold circuit and the output of the second track and hold circuit. Moreover, an input of a third summing circuit coupled to an output of a modulator and an output of the second summing circuit, and an output of the third summing circuit coupled to an input of the first amplifier.

An amplifier circuit a differential input stage coupled to a first input and to a second input between which a differential input voltage is present. A converter stage is coupled to the input stage to convert the differential input voltage into a converted voltage. An output stage is coupled to the converter stage and generates, starting from the converted voltage, an output voltage on a single output of the amplifier circuit. A biasing stage is coupled to the input stage and to the output stage to supply a biasing current. A chopper module reduces a contribution of offset and noise associated with the output voltage. The chopper module is coupled to the input stage, converter stage, and to the biasing stage. The chopper module includes an input chopper stage, a converter chopper stage, and a biasing chopper stage that operate jointly under control of a chopper signal.

Disclosed examples include differential amplifier circuits and variable neutralization circuits for providing an adjustable neutralization impedance between an amplifier input node and an amplifier output node, including neutralization impedance T circuits with first and second impedance elements in series between the amplifier input and output, and a third impedance element, including a first terminal connected to a node between the first and second impedance elements, and a second terminal connected to a transistor. The transistor operates according to a control signal to control the neutralization impedance between the amplifier input node and the amplifier output node.

An output of a first amplifier is coupled to an input of a first track and hold circuit and an input of a second track and hold circuit. An input of a first summing circuit is also coupled to an output of the first track and hold circuit and an output of the second track and hold circuit. In addition, an input of a second summing circuit is coupled to the output of the first track and hold circuit and the output of the second track and hold circuit. Moreover, an input of a third summing circuit coupled to an output of a modulator and an output of the second summing circuit, and an output of the third summing circuit coupled to an input of the first amplifier.

An amplifier circuit a differential input stage coupled to a first input and to a second input between which a differential input voltage is present. A converter stage is coupled to the input stage to convert the differential input voltage into a converted voltage. An output stage is coupled to the converter stage and generates, starting from the converted voltage, an output voltage on a single output of the amplifier circuit. A biasing stage is coupled to the input stage and to the output stage to supply a biasing current. A chopper module reduces a contribution of offset and noise associated with the output voltage. The chopper module is coupled to the input stage, converter stage, and to the biasing stage. The chopper module includes an input chopper stage, a converter chopper stage, and a biasing chopper stage that operate jointly under control of a chopper signal.

A semiconductor device includes an operational transconductance amplifier (OTA) with a matched pair of transistors including a first transistor and a second transistor, and configuration units that include a first set of switches, a second set of switches, and an input transistor. Gain adjustment circuitry is coupled to adjust gain of the OTA. Measurement circuitry is coupled to measure offset in the OTA. Control logic is configured to operate the first and second sets of switches to couple input transistors of a first group of the configuration units to the first transistor of the matched pair of transistors, and to couple input transistors of a remaining group of the configuration units to the second transistor of the matched pair of transistors. Settings of the first and second sets of switches are selected to minimize the offset.

A semiconductor device includes an operational transconductance amplifier (OTA) with a matched pair of transistors including a first transistor and a second transistor, and configuration units that include a first set of switches, a second set of switches, and an input transistor. Gain adjustment circuitry is coupled to adjust gain of the OTA. Measurement circuitry is coupled to measure offset in the OTA. Control logic is configured to operate the first and second sets of switches to couple input transistors of a first group of the configuration units to the first transistor of the matched pair of transistors, and to couple input transistors of a remaining group of the configuration units to the second transistor of the matched pair of transistors. Settings of the first and second sets of switches are selected to minimize the offset.