A system for compensating for photodiode errors includes a live photodiode configured to be exposed to a light source and to output a live signal. The system further includes a reference photodiode located proximate to the live photodiode and configured to be isolated from the light source and to output a reference signal. The system further includes a controller configured to generate a compensated output signal by subtracting the reference signal from the live signal.

A device includes an amplifier and calibration circuitry coupled to the amplifier. The calibration circuitry is configured to receive calibration values. The calibration circuitry is also configured to generate an output value in response to receiving a timing input.

An apparatus for detecting optical signals includes a photodetector. The photodetector is reverse-biased by a first voltage and a second voltage is added to the first voltage to provide an offset equal to the second voltage for the photodetector. A first circuit is coupled to the first circuit to provide the second voltage for the photodetector and a second circuit is coupled to the first circuit to provide the first voltage to the photodetector to reverse-bias the photodetector. The second circuit provides an output voltage proportional to a current of the photodetector at an output of the second circuit.

A receiver includes a signal receiving part suitable for outputting a signal corresponding to a reception signal that is received through an input terminal, and controlling a DC voltage of a signal to be outputted, according to an offset signal, an amplifying part suitable for amplifying and outputting an output of the signal receiving part, and a feedback control part suitable for controlling the offset signal according to an output of the amplifying part.

A transimpedance amplifier circuit includes a feedback control loop that generates a compensation current at an input of a transimpedance amplifier. The feedback control loop includes a differential integrator with an integration capacitor. A time constant associated with charging the integration capacitor is variable as a function of a pre-charge control signal. During a pre-charge phase, the pre-charge control signal is set to a first value so as to set the time constant associated with charging the integration capacitor to a first time constant value. During an operation phase, the pre-charge control signal is set to a second value so as to increase the time constant associated with charging the integration capacitor to a second time constant value greater than the first time constant value for the pre-charge phase.

An amplifier comprising a differential amplifier configured to be provide a comparator function, and a gain trimming circuit is electrically configured to provide gain trimming using a T-network comprising a varistor element. In addition, a method of trimming the gain of a differential amplifier, comprising the steps of a first step, (a) providing the differential amplifier comprising resistors in both of its paths, a second step, (b) providing a varistor in a T-network between both said paths; and lastly, a third step, (c) trimming the gain of the differential amplifier by adjusting the varistor's resistance.

Aspects of the disclosure provide an amplifier system and a method for dynamically cancelling an offset voltage. The amplifier system includes a chopper amplifier system that includes a differential amplifier with an offset calibration circuit. The chopper amplifier system is configured to generate an output signal including voltage variations indicating an offset voltage of the differential amplifier. The amplifier system also includes a feedback circuit configured to determine a polarity of the offset voltage of the differential amplifier based on the output signal, and to transmit a control signal to the offset calibration circuit to reduce the offset voltage of the differential amplifier.

A receiver includes a signal receiving part suitable for outputting a signal corresponding to a reception signal that is received through an input terminal, and controlling a DC voltage of a signal to be outputted, according to an offset signal, an amplifying part suitable for amplifying and outputting an output of the signal receiving part, and a feedback control part suitable for controlling the offset signal according to an output of the amplifying part.

A feedback amplifier having an improved feedback network including two cross coupled switches that isolate the amplifier from extraneous undesired electrical signals present in a system or network when the amplifier is turned off (i.e., in an off-state). The cross coupled switches interconnect two feedback paths of a feedback network to enable out-of-phase differential signals to be summed and effectively canceled. Further, the feedback amplifier provides on-stage advantages to enable different amplifier characteristics and parameter to be selectively engaged by turning on or turning off certain feedback networks.

A digital-to-analog converter (DAC) may include a conversion block providing a first analog value. The DAC may also include an amplification block for receiving the first analog value and providing a second analog value amplified by an amplification factor. The amplification block may include a first input terminal for receiving the first analog value, a second input terminal, and an output terminal for providing the second analog value. The amplification block may also include a first capacitive element and a second capacitive element. The first and second capacitive elements may determine the amplification factor. The amplification block may further include a control unit for recovering a charge at a first terminal of the second capacitive element, and based thereon, the second analog value.