Methods and systems are described that include a differential amplifier driving an active load circuit, the active load circuit having a pair of load transistors and a high-frequency gain stage providing high frequency peaking for the active load circuit according to a frequency response characteristic determined in part by resistive values of a pair of active resistors connected, respectively, to gates of the pair of load transistors, and a bias circuit configured to stabilize the high frequency peaking of the high-frequency gain stage by generating a process-and-temperature variation (PVT)-dependent control voltage at gates of the active resistors to stabilize the resistive values of the pair of active resistors to account for PVT-dependent voltages at the gates of the pair of load transistors.

A system includes a pixel that emits light based on a signal provided to the pixel. The system may also include a buffer circuit having a differential pair stage, a cascade stage, and an output stage. The differential pair stage may receive a common mode voltage signal via a first switch in response to the first switch receiving a first signal that causes the first switch to close. The differential pair stage may couple a capacitor to the output stage via a second switch that operate based on a second signal, such that the capacitor reduces an offset provided by one or more circuit components in the differential pair stage, the cascade stage, the output stage, or any combination thereof. The differential pair stage may output the common mode voltage to the pixel via the output stage in response to the first signal being present.

An amplifier includes an amplification circuit including an input circuit receiving an input signal and configured to output an output signal by amplifying the input signal; and an offset cancelling circuit configured to cancel offset by controlling the input circuit according to activation control signal and offset control signal, wherein the offset cancelling circuit cancels the offset according to the offset control signal after the activation control signal is activated.

Embodiments presented herein provide apparatus and techniques to reduce a direct current (DC) voltage offset between a transmitter and receiver. Embodiments include a shared reference voltage signal generated by a reference voltage source. The receiver may include a first unit gain buffer to receive a reference voltage signal from the reference voltage source. The transmitter may be communicatively coupled to the receiver via one or more connections and may include a second unit gain buffer communicatively coupled to the first unit gain buffer via one of the connections. An amplifier (e.g., an operation amplifier) of the transmitter may include multiple positive inputs coupled to the second unit gain buffer and an offset tracker. The offset tracker may compensate for a DC offset caused by at least a power supply and/or a ground bounce.

Embodiments presented herein provide apparatus and techniques to reduce a direct current (DC) voltage offset between a transmitter and receiver. Embodiments include a shared reference voltage signal generated by a reference voltage source. The receiver may include a first unit gain buffer to receive a reference voltage signal from the reference voltage source. The transmitter may be communicatively coupled to the receiver via one or more connections and may include a second unit gain buffer communicatively coupled to the first unit gain buffer via one of the connections. An amplifier (e.g., an operation amplifier) of the transmitter may include multiple positive inputs coupled to the second unit gain buffer and an offset tracker. The offset tracker may compensate for a DC offset caused by at least a power supply and/or a ground bounce.

An amplifier includes a first input circuit, a second input circuit, a first compensation circuit, a second compensation circuit. The first input circuit changes a voltage level of the negative output node based on a first input signal. The second input circuit changes a voltage level of the positive output node based on a second input signal. The first compensation circuit changes the voltage level of the positive output node based on the first input signal. The second compensation circuit changes the voltage level of the negative output node based on the second output signal.

A receiver circuit has a first stage circuit having a first stage input and a first stage output, the first stage output setting a first stage common mode voltage; a second stage circuit having a second stage input connected to the first stage output, and a second stage output setting a second stage common mode voltage; and a buffer circuit having a trip point voltage, connected to the second stage output. The first stage circuit can include circuit elements configured to establish the first stage common mode voltage so that the second stage common mode voltage matches the trip point voltage. The second stage circuit can include a self-biased amplifier.

An equalizer having a split folded cascode architecture includes a circuit having a differential pair with a single tail current source and split folded cascode branches. The single tail current source eliminates the input referred offset due to a mismatch in current sources. The folded cascode amplifier acts as the equalizer, which is split into a derivative path and a proportional path. The derivative path boosts the high frequency components of the received signal. The gain of the low frequency components of the received signal is adjusted by the proportional path. The derivative path includes variable capacitors and variable resistors which allow fixing a ‘zero’ frequency and peak gain frequency to a predetermined value, wherein frequencies greater than the ‘zero’ frequency are boosted. The proportional path includes variable resistors, which allow adjusting the low frequency gain without affecting the ‘zero’ frequency and peak gain frequency.

An equalizer having a split folded cascode architecture includes a circuit having a differential pair with a single tail current source and split folded cascode branches. The single tail current source eliminates the input referred offset due to a mismatch in current sources. The folded cascode amplifier acts as the equalizer, which is split into a derivative path and a proportional path. The derivative path boosts the high frequency components of the received signal. The gain of the low frequency components of the received signal is adjusted by the proportional path. The derivative path includes variable capacitors and variable resistors which allow fixing a ‘zero’ frequency and peak gain frequency to a predetermined value, wherein frequencies greater than the ‘zero’ frequency are boosted. The proportional path includes variable resistors, which allow adjusting the low frequency gain without affecting the ‘zero’ frequency and peak gain frequency.

A thermally-isolated-metal-oxide-semiconducting (TMOS) sensor has inputs coupled to first and second nodes to receive first and second bias currents, and an output coupled to a third node. A tail has a first conduction terminal coupled to the third node and a second conduction terminal coupled to a reference voltage. A control circuit applies a control signal to a control terminal of the tail transistor based upon voltages at the first and second nodes so that a common mode voltage at the first and second nodes is equal to a reference common mode voltage. A differential current integrator has a first input terminal coupled to the second node and a second input terminal coupled to the first node, and provides an output voltage indicative of an integral of a difference between a first output current at the first input terminal and a second output current at the second input terminal.