Hi,
in general voltage amplifying circuit, it's clear to calculate the closed loop bandwidth to be GBW/gain.
But if I configure a OPA188 as a current to voltage circuit(TIA). How can I calculate the signal bandwidth that could pass from input to output?
I don't know how to calculate the parameter gain.
Hey Justifice, a simplified solution for a Butterworth response is in several of the higher speed datasheets, but would also apply to the OPA188, here is the start of that in the OPA838 datasheet with the equations down below this,
And actually, some recent work I was doing enhanced the GBP idea for just a voltage gain - the old GBP idea never did work very well at low gains,
https://www.planetanalog.com/why-is-amplifier-gbp-so-confusing-insight-12/
Justifice,
The bandwidth of TIA is a function of several factors and is typically set by the RF and CF - see below.
Below please find TIA typical AC response, which have to carefully control fz and fp to assure stable operation.
In order to understand TIA bandwidth and what goes into assuring TIA stability, please read the article below:
