A balanced differential transimpedance amplifier with a single-ended input operational over a wide variation in the dynamic range of input signals. A threshold circuit is employed to either or a combination of (1) generate a varying decision threshold to ensure a proper slicing over a wide range of input current signal levels; and (2) generate a bias current and voltage applied to an input of a transimpedance stage to cancel out a dependence of the transimpedance stage voltage input on input current signal levels.

The disclosure relates to an alternating current (AC) coupling circuit including first and second capacitors having first and second input terminals configured to receive an input differential signal and generate an output differential signal at first and second output terminals of the first and second capacitors. The AC coupling circuit further includes a baseline wander correction circuit configured to make the output differential signal resistant to baseline wander due to the input differential signal including one or more time intervals of unbalanced data. The baseline wander correction circuit includes a differential difference amplifier (DDA) having a first differential input configured to receive the input differential signal, a differential output configured to generate a compensation differential signal, and a second differential input configured to receive the compensation differential signal. The compensation differential signal is applied to the output terminals of the first and second capacitors via a pair of resistors, respectively.

Aspects of the disclosure provide a sense amplifier that includes a first amplifying circuit, a second amplifying circuit, a coupling circuit and a detection circuit. The first amplifying circuit is configured to receive an input signal that carries digital values and amplify the input signal to generate a first output. The coupling circuit is configured to combine the input signal with an offset signal to form a combined signal. The offset signal is used to cancel an offset of the first amplifying circuit. The second amplifying circuit is configured to receive the combined signal of the input signal and the offset signal and amplify the combined signal to generate a second output. The first output and the second output are combined to form a combined output. The detection circuit is configured to detect the digital values based on the combined output.

A circuit includes a first common mode amplifier including a first input, a second input, and a first output. The first common mode amplifier comprises a first plurality of self-biased differential amplifiers. The circuit also includes a second common mode amplifier including a third input, a fourth input, and a second output, The third input is connected to the second input and the fourth input is connected to the first input. The second common amplifier comprises a second plurality of self-biased differential amplifiers. The circuit further includes a first gain amplifier including a fifth input and a sixth input and a second gain amplifier including a seventh input and an eighth input. The first output is connected to the fifth and eight inputs and the second output is connected to the sixth and seventh inputs.

A circuit includes a first common mode amplifier including a first input, a second input, and a first output. The first common mode amplifier comprises a first plurality of self-based differential amplifiers. The circuit also includes a second common mode amplifier including a third input, a fourth input, and a second output, The third input is connected to the second input and the fourth input is connected to the first input. The second common amplifier comprises a second plurality of self-based differential amplifiers. The circuit further includes a first gain amplifier including a fifth input and a sixth input and a second gain amplifier including a seventh input and an eighth input. The first output is connected to the fifth and eight inputs and the second output is connected to the sixth and seventh inputs.

A circuit includes a first common mode amplifier including a first input, a second input, and a first output. The first common mode amplifier comprises a first plurality of self-based differential amplifiers. The circuit also includes a second common mode amplifier including a third input, a fourth input, and a second output, The third input is connected to the second input and the fourth input is connected to the first input. The second common amplifier comprises a second plurality of self-based differential amplifiers. The circuit further includes a first gain amplifier including a fifth input and a sixth input and a second gain amplifier including a seventh input and an eighth input. The first output is connected to the fifth and eight inputs and the second output is connected to the sixth and seventh inputs.

A circuit includes a first common mode amplifier including a first input, a second input, and a first output. The first common mode amplifier comprises a first plurality of self-based differential amplifiers. The circuit also includes a second common mode amplifier including a third input, a fourth input, and a second output, The third input is connected to the second input and the fourth input is connected to the first input. The second common amplifier comprises a second plurality of self-based differential amplifiers. The circuit further includes a first gain amplifier including a fifth input and a sixth input and a second gain amplifier including a seventh input and an eighth input. The first output is connected to the fifth and eight inputs and the second output is connected to the sixth and seventh inputs.

A current buffer includes: a current replication circuit for generating a first intermediate current at a first node and a second intermediate current at a second node according to an input current; a first impedance biasing circuit for providing a first input impedance at the first node and generating an output current according to a current flowing through the first node; a second impedance biasing circuit for providing a second input impedance at the second node; and a feedforward capacitor coupled between the first node and the second node. The first input impedance is lower than the second input impedance, such that a current gain between the output current and the input current has a zero and a pole which are related to the feedforward capacitor and the second input impedance. The zero has a lower frequency than the pole.