I have tried to use the ADI DiffAmpCalc to simulate performance of ADA4940.
However, I can only get bandwidth of 24MHz instead of more than 200MHz as stated in the datasheet.
Can you please indicate what went wrong in the simulator?
The DiffAmp calculator only models the large signal bandwidth. The 24MHz that you are seeing is closely correlated with the specification given in the datasheet:
The software will not be able to correctly model an input as small as the 5mV that you are using. If you would really like to see this small signal output on simulation, you can download the free Multisim Component Evaluator at this link, and try it using that software.
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