all you need to perform a .AC analysis (in an open or closed loop configuration) is to use a voltage source at the input with AC amplitude set to 1V. The DC amplitude field of the same source can be used to set the OP around which the small signal analysis is valid.
In your simulator then you choose the frequency range within which you perform the analysis
You might however ask yourself if a small signal analysis is
useful for a large signal switching circuit that may never
see the operating point of analysis.
Although I have seen and used inverters applied linear, that's
kind of a fringe application.
You can connect output to input through an iprobe block
and get the stability / gain / phase plots you want. But
whether they tell you anything ultimately useful is another
matter.
The opening post did not require a stability analysis; why insisting on having the analysis carried out in a closed loop configuration? as long as the DC level of input and output node are initialized the AC analysis will have meaning
Even if this were not a real world application (which you are disputing yourself), it is still good enough to learn how to run an AC analysis.
You will get what's the gain and phase delay for small signals around your OP, how is that not good enough?
Dude this forum is full of beginners if they are not good enough for you just do not answer
---------- Post added at 12:44 ---------- Previous post was at 12:39 ----------
Hi kudret
all you need to perform a .AC analysis (in an open or closed loop configuration) is to use a voltage source at the input with AC amplitude set to 1V. The DC amplitude field of the same source can be used to set the OP around which the small signal analysis is valid.
In your simulator then you choose the frequency range within which you perform the analysis
I have to say that the description of the AC analysis is a bit iffy, you do not need a vsin source to run an AC analysis... still it should work as long as you have set in it some value for 'DC Amplitude'
I have to say that the description of the AC analysis is a bit iffy, you do not need a vsin source to run an AC analysis... still it should work as long as you have set in it some value for 'DC Amplitude'
It looks to me like your output is shorted to the input... plot both magnitude and phase of the output and increase the frequency range to 1GHz, make sure your input DC Amplitude is set somewhere midrail, and post a plot of the simulation of the annotated simulation schematic (larger than the last one)