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Simulators >> Circuit Simulators >> ngspice problems
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Message started by kiltanen on Sep 30^th, 2016, 1:04am

Title: ngspice problems
Post by kiltanen on Sep 30^th, 2016, 1:04am

I'm running ngspice in batch mode and have following commands in my netlist
.AC LIN 10000 950e3 1300000
.PLOT AC VM(no6)

I get following error: Note: No ".plot", ".print", or ".fourier" lines; no simulations run

How can I fix this?

Title: Re: ngspice problems
Post by Geoffrey_Coram on Sep 30^th, 2016, 11:25am

Could it be as simple as needing to have the .plot before the .ac?

Title: Re: ngspice problems
Post by kiltanen on Oct 1^st, 2016, 10:26am

I finally got got the simulation running after I fixed the issues with the netlist, but the simulation shows that ac magnitude in nodes no5 and no6 is zero. I'm attaching my netlist files in single package so someone might be able to say what is wrong with the model. I use following command to run the simulation: ngspice -b -o rspice.log resonaattorit.cir

Title: Re: ngspice problems
Post by Holger on Oct 5^th, 2016, 8:54am

Node no4 has a DC source connected to ground. During AC simulation (small signal simulation) DC current sources are opened, DC voltage sources are short circuited.

Holger

Title: Re: ngspice problems
Post by kiltanen on Oct 5^th, 2016, 11:24am

the dc-source is used as bias voltage to linearize the transducers, is this possible ac analysis? how can i get the signal going though the subcircuit kytketyt_resonaattorit instead of the bias resistors? is there possibly something with the voltage controlled capacitance in NormalTransducer subcircuit? Also there is mistake in the netlist as the eta parameter of components Xs1-4 should be infinity not the same than in Xr1-4 components.