The present invention provides an amplifier circuit, wherein the amplifier circuit includes an operational amplifier and a feedback path. The operational amplifier has an input terminal and an output terminal, and is arranged for receiving an input signal to generate an output signal. The feedback path is coupled between the input terminal and the output terminal of the operational amplifier, wherein the feedback path comprises at least two poly resistors, and a depletion region of at least one of the two poly resistors is biased by the output signal generated by the operational amplifier.

A signal amplifier includes a first amplifier, a second amplifier, and an output. The first amplifier amplifies a first input signal to form a first amplified output signal. The first input signal has a common mode voltage in a first voltage range, and the first amplified output signal has a common mode voltage in a second voltage range different from the first voltage range. The second amplifier amplifies a second input signal to form a second amplified output signal. The first input signal has the common mode voltage in the second voltage range and the second amplified output signal has the common mode voltage in the second voltage range. The output outputs the first amplified output signal or the second amplified output signal as an amplified output signal.

The disclosed embodiments relate to the design of a system that implements a coupling balance scheme for differential signals. The system includes a set of 2N signal lines carrying N differential signal pairs, wherein the set of 2N signal lines runs parallel to each other in a planar layout. The set of 2N signal lines is organized into a set of consecutive sequences, wherein each sequence includes a pattern of twists that switch signal positions for each differential pair to cancel coupling effects with respect to other signal lines. Moreover, the positions of differential signal pairs are exchanged between consecutive sequences, so that the set of consecutive sequences includes a sequence for each possible ordering of the N differential signal pairs.

In a general aspect, a system can include a fully differential amplifier circuit that includes a first amplifier, and first and second feedback paths. The first feedback path can provide a feedback path from a positive output of the first amplifier to a negative input of the first amplifier. The second feedback path can provide a feedback path from a negative output of the first amplifier to a positive input of the first amplifier. The system can include a chopper clock circuit configured to output a variable duty cycle chopper clock signal. The system can include a common mode loop circuit including a second amplifier and chopper switches. The common mode loop circuit can be configured as a local feedback loop for the first amplifier. The chopper switches can be configured to receive the chopper clock signal and control current flow into the positive and negative inputs.

A comparator includes a resolver controlled by a resolver clock signal and a differential amplifier controlled by a sampling clock signal. The resolver clock signal and the sampling clock signal are such that amplification at the differential amplifier during the reset phase of the resolver clock signal and the reset phase of the sampling clock signal begins during the resolving phase of the resolver.

A device for converting a photonic signal to be analyzed includes two output branches, and one input for receiving a photonic signal to be analyzed and splitting off a part of the photonic signal to each output branch. The device imposes a phase shift of approximately 180 degrees between the two parts, each output branch including a photodiode generating a respective first electrical current. Each output branch generates a second electrical current according to a value of the first current of the branch considered. The device also includes an amplifier generating an output signal according to a difference between the values of the second currents, a gain being defined for each output branch, and at least one electronically controlled adjustment element configured to modify one of the gains.

An example continuous time linear equalizer (CTLE) includes a first inverter; a second inverter having an input to receive an input signal; a capacitor coupled between an input of the first inverter and the input of the second inverter; a resistor coupled between a common-mode voltage and the input of the first inverter; a third inverter having an output to provide an output signal; and a node comprising an output of the first inverter, an output of the second inverter, an input of the third inverter, and the output of the third inverter.

The invention relates to a device for converting a photonic signal to be analyzed, comprising two output branches, one input for receiving a photonic signal to be analyzed and splitting off a part of the photonic signal to each output branch, the device imposing a phase shift of approximately 180 degrees between the two parts, each output branch including a photodiode generating a respective first electrical current, each output branch generating a second current according to a value of the first current of the branch considered, the device comprising an amplifier generating an output signal according to a difference between the values of the second currents, a gain being defined for each output branch, the device including at least one electronically controlled adjustment element apt to modify one of the gains.

Amplifying circuitry configured such that when a detection circuit detects an abnormal state in which the level of signals input to a main amplifying circuit exceeds a normal range, a control circuit sets the state of integration of signals in the integration circuit to a default state. When the detection circuit detects the abnormal state and then detects that an operating state returns to a normal state in which the level of signals input to the main amplifying circuit is included in the normal range, the control circuit cancels the setting of the default state in the integration circuit.

An amplifier includes a differential positive input, a differential negative input, and a transistor. The transistor is communicatively coupled to the differential positive input and differential negative input at a source of the transistor. The transistor is configured to track input common mode of the differential positive input and differential negative input.