The present disclosure provides for process and temperature compensation in a transimpedance amplifier (TIA) using a dual replica via monitoring an output of a first TIA (transimpedance amplifier) and a second TIA; configuring a first gain level of the first TIA based on a feedback resistance and a reference current applied at an input to the first TIA; configuring a second gain level of the second TIA and a third TIA based on a control voltage; and amplifying a received electrical current to generate an output voltage using the third TIA according to the second gain level. In some embodiments, one or both of the second TIA and the third TIA include a configurable feedback impedance used in compensating for changes in the second gain level due to a temperature of the respective second or third TIA via the configurable feedback impedance of the respective second or third TIA.

A differential amplifier includes an unmatched pair, including first quantum dots and second quantum dots, and a matched pair, including first and second phototransistors. The unmatched pair has a difference between a first spectrum absorbed by the first quantum dots and a second spectrum absorbed by the second quantum dots. Each of the first and second phototransistors includes a channel. The first quantum dots absorb the first spectrum from incident electromagnetic radiation and gate a first current through the channel of the first phototransistor, and the second quantum dots absorb the second spectrum from the incident electromagnetic radiation and gate a second current through the channel of the second phototransistor. The first and second phototransistors are coupled together for generating a differential output from the first and second currents, the differential output corresponding to the difference between the first and second spectrums within the incident electromagnetic radiation.

A current amplifying circuit includes a first FET transistor, a light receiving unit and a functional unit. The light receiving unit is connected with a first gate terminal of the first FET transistor through an enabling line. The functional unit is connected with a second conduction terminal of the first FET transistor. When the light receiving unit absorbs a light beam, a forward photoelectric current or a reverse photoelectric current is generated. The forward photoelectric current or the reverse photoelectric current flows to the first gate terminal through the enabling line. Consequently, an enabling voltage at the first gate terminal is increased and the first FET transistor is turned on. When the first FET transistor is turned on, an enabling current flows through the first FET transistor to enable the functional unit.

A light detection and ranging (LIDAR) system includes an automatic gain control (AGC) unit to reduce the dynamic range, reducing processing power and saving circuit area and cost. The system detects a return beam of a light signal transmitted to a target, having a first dynamic range in a time domain. An analog to digital converter (ADC) generates a digital signal based on the return beam. A processor can perform time domain processing on the digital signal, convert the digital signal from the time domain to a frequency domain, and perform frequency domain processing on the digital signal in the frequency domain. The AGC unit can measure a power of the return beam, and apply variable gain in the time domain to reduce a dynamic range of the return beam to a second dynamic range lower than the first dynamic range.

An optical transformer includes a plurality of light emitters, a plurality of photovoltaic cells positioned to receive light from at least a first subset of the plurality of light emitters, the plurality of photovoltaic cells including at least a first photovoltaic cell and a second photovoltaic cell, and one or more optically triggered switches positioned to receive light from at least a second subset of the plurality of light emitters, the one or more optically triggered switches including at least a first optically triggered switch electrically coupled to the first photovoltaic cell and the second photovoltaic cell. A method of operating the optical transformer is also described.

An optical transformer includes a plurality of light emitters, a plurality of photovoltaic cells positioned to receive light from at least a first subset of the plurality of light emitters, the plurality of photovoltaic cells including at least a first photovoltaic cell and a second photovoltaic cell, and one or more optically triggered switches positioned to receive light from at least a second subset of the plurality of light emitters, the one or more optically triggered switches including at least a first optically triggered switch electrically coupled to the first photovoltaic cell and the second photovoltaic cell. A method of operating the optical transformer is also described.

A single servo control loop for amplifier gain control based on signal power change over time or system to system, having an amplifier configured to receive an input signal on an amplifier input and generate an amplified signal on an amplifier output. The differential signal generator processes the amplified signal to generate differential output signals. The single servo control loop processes the differential output signal to generates one or more gain control signals and one or more current sink control signals. A gain control system receives a gain control signal and, responsive thereto, controls a gain of one or more amplifiers. A current sink receives a current sink control signal and, responsive thereto, draws current away from the amplifier input. Changes in input power ranges generate changes in the integration level of the differential signal outputs which are detected by the control loop, and responsive thereto, the control loop dynamically adjusts the control signals.

A transimpedance amplifier circuit (1) includes an amplifier (22) that amplifies a received signal, an automatic gain control (AGC) circuit (2) that controls the amplification gain of the amplifier by a first time constant in accordance with the level of the received signal, and a first selection circuit (25) that selects the first time constant from a plurality of predetermined values. This can simultaneously implement a short time constant of an AGC function necessary to instantaneously respond to a burst signal and a long time constant of the AGC function necessary to obtain a satisfactory bit error rate (BER) characteristic in a continuous signal by an inexpensive and compact circuit arrangement.

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.

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.