Re: [Ngspice-users] NGSPICE Transient Analysis question

[Victor B. <vi...@ty...>]

Hi Tony,

Well, if you haven't accidentally discovered a flaw in some dimension of 
time-space continuum, then the reason may be that circuit analysis failed to 
converge during "previous" time step. The usual procedure for the simulator in 
this case is to decrease the value of time step and try again.
Thus the simulation may go through time as illustrated:
0 ms -> 10ms -> 20 ms -> 30 ms (failed) -> 25 ms (failed) -> 22.5 ms -> 25 ms -> 
and so on

How does this "backup in time" manifest itself?

Cheers,
Victor

> 
> All,
> 
> I am creating a codemodel using NGSPICE, and I have noticed during a
> transient analysis, NGSPICE will backup in time.  The current time point
> will be before the previous.  Can someone explain why/when that would
> happen?
> 
> Thanks,
> Tony
>