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I am trying to design a circuit that connects a transimpedance amplifier (TIA) and buffer amplifier (BA) using op-amps together as such that the output of TIA becomes the input of the BA. The input signal feeding the TIA is a 10KHz sine waves from the current source generator. I have tried connecting the two circuits together and simulating it but have not been getting a waveform at the output. What type of waveform should I be seeing at the output of the BA? Please help. Many thanks Tony

@s4280263,

Welcome to CL.

Referring to your circuit:

as posted 130905 (note that if you change it rather than editing a copy, it will update in your original; posting which can be confusing because the circuit no longer looks like what the posting is talking about, i.e. they get out of sync):

you have a few minor errors in your sim.

i) Your Stop Time and Time Step are way too big for a 10kHz input signal with a period of 100us!

Time Step should be approx (Stop Time) /100

Try setting Stop Time = 200u

and Time Step = 2u

ii) You are pushing 1A into OA1. Try reducing this to 1uA!

iii) Reverse the polarity of V7: you have 0V across the supply pins of OA2.

Gereral point: When asking for help, please (a) make your circuit public or unlisted (you did so that's OK) and (b) link them into your posting using the Link & Share options, so viewers can see it without having to hunt through your workbench (noting that it won't be visible there unless you've made it public).

:)

Signality, thank you so much for the head start. I will certainly amend as suggested and use Link & Share from now on. I will how it goes and update status for further help. Appreciate your help very much.