An amplifier circuit includes a voltage-to-current conversion circuit and a current-to-voltage conversion circuit. The voltage-to-current conversion circuit generates a current signal according to an input voltage signal, and includes an operational transconductance amplifier (OTA) used to output the current signal at an output port of the OTA. The current-to-voltage conversion circuit generates an output voltage signal according to the current signal, and includes a linear amplifier (LA), wherein an input port of the LA is coupled to the output port of the OTA, and the output voltage signal is derived from an output signal at an output port of the LA.

A differential amplifier is provided, in which generation of unnecessary harmonic distortion in the differential output signal is suppressed. A common mode feedback circuit increases or decreases operating points of an inverting output terminal and a non-inverting output terminal such that an intermediate voltage of voltages respectively provided to an inverting input terminal and a non-inverting input terminal is consistent with to a reference voltage. Variations in voltage at the inverting input terminal and the non-inverting input terminal are suppressed, variations in electrical properties of elements connected to the input terminals are suppressed. Therefore, it is possible to suppress generation of harmonic distortion in the output signals from the inverting output terminal and the non-inverting output terminal.

A bias structure includes a reference voltage node connected to gate structures of a first NMOS transistor and a second NMOS transistor, a bias voltage node comprising a bias voltage, and a first op amp having a first input connected to the reference voltage, a second input connected to a drain of the first NMOS transistor, and an output connected to gate structures of a first PMOS transistor and a second PMOS transistor. The bias structure further includes a second op amp having a first input connected to the reference voltage, a second input connected to a drain of the second NMOS transistor, and an output connected to a gate structure of a third NMOS transistor and the bias voltage node. The first NMOS transistor matches a transistor of a differential pair of an integrated circuit device.

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 be utilized in a digital-to-analog converter. The amplifier circuit may comprise a first operational amplifier with a feedback circuit. The feedback circuit may comprise an inverting amplifier circuit.

The present disclosure provides a clock driver circuit, including: an input stage, a double-ended to single-ended conversion stage and a driver output stage connected in sequence. The input stage includes two mutually loaded differential amplifiers and a common mode negative feedback loop. The differential amplifiers are connected to a differential clock signal for amplification to generate a common mode voltage. The common mode feedback circuit is connected to an output end of the differential amplifiers to stabilize the output amplitude of the common mode voltage. The double-ended to single-ended conversion stage converts a differential sine clock signal output by the double-ended common mode voltage into a single-ended square wave clock signal. The driver output stage includes a multi-stage cascaded push-pull phase inverter to improve the drive capability of the square wave clock signal.

An amplifier circuit includes a voltage-to-current conversion circuit and a current-to-voltage conversion circuit. The voltage-to-current conversion circuit generates a current signal according to an input voltage signal, and includes an operational transconductance amplifier (OTA) used to output the current signal at an output port of the OTA. The current-to-voltage conversion circuit generates an output voltage signal according to the current signal, and includes a linear amplifier (LA), wherein an input port of the LA is coupled to the output port of the OTA, and the output voltage signal is derived from an output signal at an output port of the LA.

Various embodiments of the present technology may provide methods and apparatus for an amplifier integrated circuit. The amplifier integrated circuit may provide two amplifiers, one amplifier set to a low gain bandwidth product to amplify at a higher speed and the other amplifier set to a high gain bandwidth product to amplify at a lower speed. The amplifier integrated circuit may further provide a switching circuit connected to the amplifiers, wherein the switching circuit is responsive to a control signal and operates to selectively activate the high speed amplifier and the low speed amplifier in sequence.

A fully differential amplifier includes: an input stage comprising a first amplification circuit and a second amplification circuit, one of which is configured to generate a push signal and the other of which is configured to generate a pull signal, each by amplifying a differential input signal; an output stage for generating a differential output signal based on the push signal and the pull signal; and a feedback circuit for providing common mode feedback to the first amplification circuit based on the differential output signal, wherein the second amplification circuit may include a passive network for setting a common mode voltage of the push signal or the pull signal.

Systems with object detection capabilities may include a radio detection and ranging (RADAR) system. The RADAR system or other portions of the systems may include analog-to-digital converter circuitry. The analog-to-digital converter circuitry may be implemented as pipeline analog-to-digital converter circuitry having multiple stages. Each stage may include multiplying digital-to-analog converter circuitry having a sampling network and amplifier circuitry. The amplifier circuitry may be shared be shared between multiple stages. The amplifier circuitry may include cascodes for switching between different input pairs from corresponding sampling networks in corresponding stages. The amplifier circuitry may generate amplifier outputs for a first sampling network while the other sampling network performs sampling operations. This may minimize non-amplification time for the amplifier circuitry reduce power consumption in the converter circuitry. The amplifier circuitry may also include shorting switches that bring the amplifier output to a common mode voltage to more improve output slew characteristics.

Memories for receiving or transmitting voltage signals might include an input or output buffer including a first stage having first and second inputs and configured to generate a current sink and source at its first and second outputs responsive to a voltage difference between its first and second inputs, and a second stage having a first input connected to the first output of the first stage, a second input connected to the second output of the first stage, a first voltage signal node connected to its first input through a first resistance, and a second voltage signal node connected to its second input through a second resistance, wherein a first inverter is connected in parallel with the first resistance, a second inverter is connected in parallel with the second resistance, and a pair of cross-coupled inverters are connected between the first voltage signal node and the second voltage signal node.