Small Signal Step Response

[jaydnul]

Kind of an interesting question, I want to look at a small signal 1V step response in a similar way we look at a small signal 1V magnitude AC response. The easiest way to do this in my mind is run an AC analysis and do an inverse DFT, but it doesnt seem to be working for me.

Has anyone else tried something like this, just out of curiosity? If so how did you do it

 

[FvM]

Surely possible. Inverse FT of flat and linear phase frequency response is delta impulse, need to be integrated once to get step function.

In simulator, it's probably most simple to perform a transient analysis with sufficient low magnitude (mV range).

Which problem do you experience?

 

[BigBoss]

Frequency Domain and Time Domain functions can be converted by Convolution Theorem/Integral.
That's why they are related.
I hope understood well your comments.

 

[jaydnul]

ah ok, thanks all. I found a function called foureval which does the inverse dft. I have a related question about cadence calculator itself, if i do a dft on a time domain signal i get back a discrete plot shown in the first picture. Is there an easy way to convert a continous frequency domain plot (second picture) into a discrete one that looks like the first picture? The sample function will connect the dots and still make the plot continous which i dont want