I'm currently using LTspice, and I have a problem with it "never" finishing calculating a certain circuit. When I say "never", I mean that it's still calculating an hour after it started, even though the review-time is less than two periods of the input sine.
In the program status field it says: "Stepping Source: 100% step size=6.8413e-005 N-R iterations: changes frequently between numbers spanning from 0 to 200 fill-ins: 4". It seems to be stuck at this point.
The circuit I'm talking about is this frequency doubler.
Does anybody know a solution to this problem? If there is no solution, can you suggest a program that will not get stuck like this?