bode plot instrument reading differs when compared to grapher plot

[educ]

Good Day,

Need some help to understand why the bode plot instrument plot (clicking the instrument to see plot) is different from the grapher plot when run in "simulate >>> analysis >>> AC analysis >>> vertical scale (db) >>> simulate.

Problem happens if the AC source AC analysis magnitude is changed from 1(default) to another value. i.e 6.

Please help advise, it seems the bode plotter is only considering the default AC analysis default magnitude value of 1?.

Appreciate comment on this. Thank you

The circuit being simulated is AC source connected to an RLC circuit and Vo is accross C. L and C assume some small series resistances.

[Tayyab_R]

Hi educ,

Can you post your circuit so we can take a look at what can be causing this issue.

[educ]

Hi,

Please see attached file.

[educ]

Hi Tayyab R, have you noticed anything unusual on my circuit that caused this problem on the bode plotter?

[Tayyab_R]

Hi educ,

In the AC Analysis I set the stop frequency to 100 KHz which is the stop frequency of the Bode Plotter instrument. When I ran the analysis after doing this and compared it to the bode plotter, it was a nearly identical output. Try to configure the start and stop frequency to match in the AC Analysis and in the Bode Plotter and you should see much better results.