Frequency domain simulation in Pspice

[Eli]

Hi peaple,

I try to build pspice simulation to a curcuit which I designed in
Orcad. The simulation should be in Frequency domain. In "Simulation
settings" I selected AC sweep option, logarithmic(decade) AC sweep
type.

Start F=10
End F=100k
Points/Decade=100.
Unfortunately the simulation is failed because of the following:
no AC sources - AC sweep ignored.

But AC source is defined(Vsin) ! The only thing I think may be the
problem is the AC source in the Orcade shematics has a defined
frequency. Am I right ?
How can I fix the problem ?

Thanks in advance,

Eli.

 

[Jim Thompson]

Hi peaple,

I try to build pspice simulation to a curcuit which I designed in
Orcad. The simulation should be in Frequency domain. In "Simulation
settings" I selected AC sweep option, logarithmic(decade) AC sweep
type.

Start F=10
End F=100k
Points/Decade=100.
Unfortunately the simulation is failed because of the following:
no AC sources - AC sweep ignored.

But AC source is defined(Vsin) ! The only thing I think may be the
problem is the AC source in the Orcade shematics has a defined
frequency. Am I right ?
How can I fix the problem ?

Thanks in advance,

Eli.

"VSIN" isn't an AC source, it's a sine wave voltage source.

Use part "VAC" (although you can still use "VSIN" but add AC=1 in the
selections).

Also make sure your .AC calls the source by its _reference_name_!

...Jim Thompson

 

[Eli]

Dear Jim,

Thank you very much for your helpful advice. Now the problem is solved.
But would you please explain me the meaning of the AC=1 selection ?

Best Regads,

Eli.

 

[Jim Thompson]

Dear Jim,

Thank you very much for your helpful advice. Now the problem is solved.
But would you please explain me the meaning of the AC=1 selection ?

Best Regads,

Eli.

Normalization... "1" = 0dB

For experiment sake, change to AC=0.1 and see what you get.

...Jim Thompson