I'm in the process of trying to build an analog synth. So far I've managed to get a VCO working on my breadboard. But I wanted to try and simulate it (and other parts of the synth) using Multisim 2001. I want to do this because I want to add a filter VCA etc and would like to try out a few different schematics from old analog designs.
HOWEVER I'm finding that when I build exactly the same circuit (VCO) using Multisim 2001 that the F$&*ing thing doesn't do what it's supposed to. I even tried Electronics Workbench v5 and still could not emulate what I'd already bulit.
So I'm wondering if anyone can help by suggesting another program that might succesfully simulate my circuits. Or maybe suggest something I may be doing wrong. Prefferably something easy to use. I played with Protel and didn't like that one.
The closest to reality simulation available is Saber. (good luck getting it). PSpice has similar convergency problems as Multisim. You can still do few things with Multisim. Try to modify Multisim transient simulation properties (miscelaneous):
increase reltol to 0.05; change the integration method to "gear" and reduce rshunt to 1e8.
Pspice is good at device level simulation, however, on system level Saber is much better. It is powerful and flexible, and easy to control convergence problem. Besides electrical domain, it can simulate other domains such as thermal as well.