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Title
a

ALOK PRATAP SINGH

03/23/2023, 11:17 AM
hi all, I wants do get gain vs frequency response. How do i get ? I tried please check @srinivasan_muthukrishnan19 @Piyush Dwivedi hi @Stefan Schippers could you help me here ? I am doing ac analysis but getting as transient. like time domain vs gain. I need a plot frequency vs gain. How can I do ?
s

Stefan Schippers

03/24/2023, 10:02 AM
you have a tran and an AC analysis.you must select the ac analysis to plot ac results.
echo $plots
setplot ac1
c

Charly Meyer

03/24/2023, 4:02 PM
tran simulation and ac simulation are lunch in same time. AC simulation is just ignored
s

Stefan Schippers

03/25/2023, 12:18 AM
I try to repeat. Before giving the
plot
command you must give the command
setplot ac1
otherwise you are seeing the output voltage and phase of a transient simulation, because this is the last simulation ran by ngspice. Since transient data is real and not complex phase is always zero,
Another simple possibility is to comment out the
tran
line and the
write
command after tran (and the
set appendwrite
)
s

srinivasan_muthukrishnan19

03/28/2023, 9:49 AM
@Stefan Schippers can we skip setplot ac1 if we run just ac analysis?
s

Stefan Schippers

03/28/2023, 10:45 AM
Yes the current plot is always the last simulation done.