Obtaining a bias control signal at a current source and responsively generating a fixed current, receiving a differential voltage input signal at corresponding differential input nodes of a plurality of differential amplifier stages connected to the current source, the plurality of differential amplifier stages comprising a primary amplifier stage and a set of supplemental amplifier stages, each of the plurality of differential amplifier stages having a pair of output nodes connected to common load impedances, generating an amplified differential voltage output signal on the pair of output nodes by directing the fixed current through the load impedances, and selectively connecting each supplemental amplifier stage in parallel to the primary amplifier stage via a corresponding gain control switch of a set of gain control switches connected to the primary amplifier stage and the plurality of supplemental amplifier stages to adjust an overall transconductance of the plurality of differential amplifier stages.

An apparatus is disclosed for processing a signal with a divided amplifier. In example implementations, an apparatus includes a first portion of an amplifier, a first port interface, a second port interface, and a switch matrix. The first port interface includes a first transformer; a second portion of the amplifier, which is coupled to the first transformer; and a first switch component that is coupled to at least one of the first transformer or the second portion of the amplifier. The second port interface includes a second transformer and a second switch component that is coupled to the second transformer. The switch matrix is coupled between the first switch component and the first portion of the amplifier and between the second switch component and the first portion of the amplifier. The switch matrix is also coupled between the second portion of the amplifier and the first portion of the amplifier.

Multi-stage auto-zeroing signal amplifiers are deployed within event-shuttering pixels of a quanta image sensor (QIS) pixel array to enable reliable per-pixel reporting of photonic events, down to resolution of a single photon strike, for each of a continuous sequence of sub-microsecond event-detection intervals.

Circuits and methods for achieving good AM-AM and AM-PM metrics while achieving good power, PAE, linearity, and EVM performance in an amplifier. Embodiments provide an equalization approach which compensates for AM-AM and AM-PM variations in an amplifier by controlling bias voltage versus output power to alter the AM-AM and AM-PM profiles imposed by the amplifier. Differential amplifier embodiments include cross-coupled common-gate transistors that generate an equalization voltage that alters the gate bias voltage of respective main FETs in proportion to a power level present at the respective drains of the main FETs. Single-ended amplifier embodiments include an equalization circuit that alters the bias voltage to the gate of a main FET in proportion to a power level present at the main FET drain. Embodiments may also include a linearization circuit which alters the AM-PM profile of an input signal to compensate for the AM-PM profile imposed by a coupled amplifier.

Apparatuses, systems, and methods for compensated sense amplifier with crosscoupled n-type transistors. A sense amplifier has a pair of p-type transistors coupled between a system voltage and respective first and second gut nodes. When a command signal is active, the p-type transistors are coupled in a diode fashion from the system voltage to the respective gut nodes. The amplifier also has a pair of n-type transistors which are cross coupled, where a first n-type transistor has a node coupled to the first gut node and a gate coupled to the second gut node and the second n-type transistor has a node coupled to the second gut node and a gate coupled to the first gut node. Each of the n-type transistors may have a separate current flowing through them and respective one of a pair of feedback transistors to a ground voltage.

A high-speed comparator circuit is provided. The circuit includes an amplifier portion, a latch portion, and a negative capacitance portion. The amplifier portion includes an input coupled to receive an analog signal and an output. The latch portion is coupled to the amplifier portion. The latch portion is configured to provide at the output a digital value based on the analog signal. The negative capacitance portion is coupled to the output. The negative capacitance portion is configured to cancel parasitic capacitance coupled at the first output.

Differential amplifier circuitry including: first and second main transistors of a given conductivity type: and first and second auxiliary transistors of an opposite conductivity type, where the first and second main transistors are connected along first and second main current paths passing between first and second main voltage reference nodes and first and second output nodes, respectively, with their source terminals connected to the first and second output nodes, respectively, and with their gate terminals controlled by component input signals of a differential input signal; and the first and second auxiliary transistors are connected along first and second auxiliary current paths passing between first and second auxiliary voltage reference nodes and the first and second output nodes, respectively, with their drain terminals connected to the first and second output nodes, respectively, and with their gate terminals controlled by the component input signals of the differential input signal.

Differential amplifier circuitry including: first and second main transistors of a given conductivity type; and first and second auxiliary transistors of an opposite conductivity type, where the first and second main transistors are connected along first and second main current paths passing between first and second main voltage reference nodes and first and second output nodes, respectively, with their source terminals connected to the first and second output nodes, respectively, and with their gate terminals controlled by component input signals of a differential input signal; and the first and second auxiliary transistors are connected along first and second auxiliary current paths passing between first and second auxiliary voltage reference nodes and the first and second output nodes, respectively, with their drain terminals connected to the first and second output nodes, respectively, and with their gate terminals controlled by the component input signals of the differential input signal.

Circuits and methods for achieving good AM-AM and AM-PM metrics while achieving good power, PAE, linearity, and EVM performance in an amplifier. Embodiments provide an equalization approach which compensates for AM-AM and AM-PM variations in an amplifier by controlling bias voltage versus output power to alter the AM-AM and AM-PM profiles imposed by the amplifier. Differential amplifier embodiments include cross-coupled common-gate transistors that generate an equalization voltage that alters the gate bias voltage of respective main FETs in proportion to a power level present at the respective drains of the main FETs. Single-ended amplifier embodiments include an equalization circuit that alters the bias voltage to the gate of a main FET in proportion to a power level present at the main FET drain. Embodiments may also include a linearization circuit which alters the AM-PM profile of an input signal to compensate for the AM-PM profile imposed by a coupled amplifier.

An electronic-system for implementing decision-feedback equalization (DFE) includes a first stage including a first-amplifier. The first amplifier including an in-built adder circuit. The first amplifier being configured to charge one or more output nodes of the first amplifier to a first voltage using a summed signal based on input data and a feedback signal in response to a first-clock variation, wherein the feedback signal is a partially-regenerated analog output from a regenerating amplifier. A second stage is includes a second amplifier configured as the regenerating amplifier and connected to the one or more output nodes of the first amplifier, the second amplifier configured to amplify charged output nodes of the second stage to a second voltage in response to a second-clock variation and apply a regenerative gain to the amplified second-voltage during the second-clock variation to generate the partially-regenerated analog output. A third stage includes a slave latch that is configured to resolve the partially-regenerated analog output at the output nodes of the second stage into non-return to zero (NRZ) digital values at an output of the third stage.