An output buffer of a super source follower for driving a reference ramp signal of a column-parallel single slope type ADC of a solid-state imaging device is made as a class AB feedback configuration for controlling a feedback variable current source with a signal obtained by amplifying a current fluctuation flowing through an amplification transistor by an amplifier, and thereby, the upper limit of the drain voltage of the amplification transistor is not limited by the voltage between the gate and the source of the feedback variable current source.

There is provided an optical communication device capable of minimum suppressing inter-signal interference of inductors mounted to enable a transmission signal to be transmitted and received with a high frequency. The optical communication device comprises a sub-package as a subassembly in each of a plurality of signal channels. The sub-package includes a substrate on which an optical semiconductor and an IC are flip-chip connected. The optical semiconductor includes a pair of photodiodes receiving a differential optical signal and outputting a differential current signal. The IC includes a transimpedance amplifier converting the differential current signal from the optical semiconductor to a voltage signal. The optical semiconductor has a pair of inductors formed for each of the pair of photodiodes and a ground wiring formed so as to surround the formed pair of inductors.

A transimpedance amplifier is provided for converting a current between its two input terminals to a voltage over its two output terminals comprising a high-speed level shifter configured for creating a difference in input DC voltage and for being transparent for alternating voltages, an input biasing network configured for reverse biasing a photodiode connected to at least one of the input terminals and transparent for a feedback signal from the feedback network which is differentially and DC-coupled with the output terminals of the voltage amplifier and outputs of the feedback network are differentially and DC-coupled with the input biasing network of which outputs are coupled with inputs of the level shifter which is differentially and DC-coupled with input terminals of the voltage amplifier.

A sensor is provided. A first terminal of a first current source and a first terminal of a first transistor are connected to a cathode of the photodiode. A control terminal of a second transistor is connected to an output terminal of a first operational amplifier. A first terminal of the second transistor is connected to a second terminal of the first transistor through a first current mirror circuit. A second terminal of the second transistor is connected to a second current source, a second input terminal of a second operational amplifier and a first terminal of a third transistor. A first input terminal of the second operational amplifier is connected to the first terminal of the first transistor. A control terminal of the third transistor is connected to an output terminal of the second operational amplifier.

A multi-stage transimpedance amplifier (TIA) with an adjustable input linear range is disclosed. The TIA includes a first stage, configured to convert a single-ended current signal from an optical sensor of a receiver signal chain to a single-ended voltage signal, and a second stage, configured to convert the single-ended voltage signal provided by the first stage to a differential signal. In such a TIA, the input linear range may be adjusted using a clamp that is programmable with an output offset current to keep the second stage of the TIA from overloading and to maintain a linear transfer function without compression.

Voltage-to-current converters that include two current mirrors are disclosed. In an example voltage-to-current converter each current mirror is a complementary current mirror in that one of its input and output transistors is a P-type transistor and the other one is an N-type transistor. Such voltage-to-current converters may be implemented using bipolar technology, CMOS technology, or a combination of bipolar and CMOS technologies, and may be made sufficiently compact and accurate while operating at sufficiently low voltages and consuming limited power.

Examples described herein relate to an analog front-end (AFE). The AFE includes a trans-impedance amplifier to receive an input current and generate a pair of the differential voltage signals based on the input current and a reference current. Further, the AFE includes a dynamic voltage slicer to receive the differential voltage signals at input terminals and supply digital voltages at output terminals. The dynamic voltage slicer includes a preamplifier to generate a pair of intermediate voltages based on the differential voltage signals sampled at a predetermined frequency. The dynamic voltage slicer also includes a voltage latch circuit coupled to the preamplifier, wherein the voltage latch circuit is to regenerate a pair of digital voltages based on the pair of the intermediate voltages. Moreover, the AFE includes a logic latch coupled to the dynamic voltage slicer to provide digital output states based on the pair of the digital voltages.

An apparatus includes a photodetector configured to generate an electrical current based on received illumination. The apparatus also includes a capacitor transimpedance amplifier (CTIA) unit cell having (i) an amplifier configured to receive the electrical current and a reference voltage, (ii) a feedback capacitor coupled in parallel across the amplifier, and (iii) a reset switch coupled in parallel across the feedback capacitor. The apparatus further includes an event detector configured to sense a high-energy event affecting the photodetector. In addition, the apparatus includes a switchable clamp coupled across inputs of the amplifier, where the event detector is configured to close the switchable clamp in response to sensing the high-energy event.

This application relates to transimpedance amplifier (TIA) apparatus, in particular to a TIA apparatus suitable for receiving data using burst mode communication. The apparatus has a transimpedance amplifier configured to generate a first voltage based on a current at an input node for an input signal. A controlled voltage source, such as a dummy TIA, generates a second voltage based on a first control current. A controller is configured to collectively control the first control current and a second control current based on an indication of input signal magnitude. The first control current controls the second voltage which may be used as a slicing level. The second control current is subtracted from the current at the input node and can provide a DC restore current.

The disclosed scanner for detecting a decay time of light emitted by a luminescent material has a control unit operable to adapt the drive current, or the value of the drive voltage, powering its light source to accordingly adapt the intensity of excitation light delivered to the luminescent material so that its high sensitivity light sensor can reliably measure the luminescence light emitted in response to the excitation light, and thus accurately determine a corresponding decay time value.