A chopper amplifier and method of operation are described. The chopper amplifier comprises a first chopper arranged to modulate an input signal using a first chopper signal having a chopper frequency. An amplification stage has an input arranged to receive the chopped signal and an output, and supplies an amplified signal at the output. An output chopper is arranged to integrate the amplified signal using a second chopper signal having the chopper frequency to generate an amplified output signal. The amplification stage is further configured to filter the chopped signal to attenuate signal components having frequencies lower than the chopper frequency.

An operational amplifier based circuit has an operational amplifier, a feedback circuit, and a compensation circuit block. The feedback circuit is coupled between an output port and an input port of the operational amplifier. The compensation circuit block has circuits involved in stability compensation of the operational amplifier, wherein there is no stability compensation circuit driven at the output port of the operational amplifier.

Embodiments generally relate to a conversion arrangement, a driver arrangement, and a method of producing a complementary complementary metal-oxide-semiconductor (CMOS) output signal for driving a modulator device. The conversion arrangement includes a differential amplifier configured to produce a first amplified signal based on the differential input signal, and at least two transimpedance amplifiers (TIAs) coupled with respective outputs of the differential amplifier and configured to produce a second amplified signal based on the first amplified signal. Respective bias voltages for the TIAs are based on the first amplified signal. The conversion arrangement further includes a common-mode feedback arrangement coupled with outputs of the TIAs and configured to control the first amplified signal based on the second amplified signal, thereby controlling the bias voltages, wherein the complementary CMOS output signal is based on the second amplified signal.

Provided is a current-voltage conversion amplifier circuit including: a plurality of light receiving devices generating a current signal proportional to an amount of light by receiving the light; multipliers amplifying the current signal, converting the amplified current signal into a first voltage signal, outputting the amplified current signal, or outputting the converted first voltage signal; multi input amplifiers outputting first and second output voltage pairs through a process for receiving output values of multipliers and an offset voltage and amplifying the received output values and offset voltage; a multiplexing unit selecting and outputting one first and second output voltage pair among the first and second output voltage pairs outputted from multi input amplifiers; and a signal conversion unit converting a difference value between first and second output voltages outputted from the multiplexing unit and outputting the converted digital signal.