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I'm in the process of designing a Transimpedance amplifier for an analytical instrument. The sample waveform (hand-drawn) is attached in the attachments. The requirement is to amplify a pulse kind of signal whose maximum amplitude is around 700 nA and the width of the pulse is around 1 ns. So, I need a high-speed transimpedance amplifier. My question is what are the opamp parameters that decide the speed of the amplifier. I need a concrete relationship between slew rate, settling time, rise time, bandwidth/gain-bandwidth. And particular to the signal which parameter is most important so that I can choose the right opamp for the design. Regards M Arivalagan enter image description here

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    \$\begingroup\$ Good luck. If you google for one, please note the price. You are probably looking for an opamp with bandwidth in excess of 5 GHz. \$\endgroup\$
    – Andy aka
    Aug 24, 2019 at 12:09
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    \$\begingroup\$ You forgot to give what gain on the output you want, this will determine the slew rate and Gain Bandwidth Produce scaling lets say you have 100MHz GBP, and a gain of 100, well then you have a Bandwidth of 1MHz, as I am assuming you would like a rather large gain you may have to approach it with a cascaded amplifier to keep the bandwidth high enough at the cost of some added noise. \$\endgroup\$
    – Reroute
    Aug 24, 2019 at 12:21
  • \$\begingroup\$ You may find this enlightening: electronicdesign.com/analog/… \$\endgroup\$ Aug 24, 2019 at 13:11
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    \$\begingroup\$ It is important to know the source impedance ( usually, the source capacitance) to design a trans impedance amplifier. More information is needed. \$\endgroup\$
    – user69795
    Jul 8, 2021 at 22:08

1 Answer 1

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Consider this: a common-base amplifier

schematic

simulate this circuit – Schematic created using CircuitLab

For more bandwidth, increase the Vce to reduce Cob; thus take +5v to +10v.

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