<@U02J59Q3FM0> If you are running a transient simu...
# analog-design
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@Nikhil M If you are running a transient simulation and the delay is in the calculation of the initial DC operating point tou can try setting all voltage sources (including supply voltages) to 0V at time=0, and then let them evolve as required for your simulation. In this case the initial DC operating point is trivially calculated (all voltages = 0). Another possibility is to force initial condition on some nodes (using the .nodeset instruction) if you know the initial state. You may also try to use the UIC option in the .tran instruction; from ngspic man: uic (use initial conditions) is an optional keyword that indicates that the user does not want ngspice to solve for the quiescent operating point before beginning the transient analysis. If this keyword is specified, ngspice uses the values specified using IC=... on the various elements as the initial transient condition and proceeds with the analysis. If the .ic control line has been specified (see 15.2.2), then the node voltages on the .ic line are used to compute the initial conditions for the devices. IC=... will take precedence over the values given in the .ic control line. If neither IC=... nor the .ic control line is given for a specific node, node voltage zero is assumed.
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@Stefan Schippers I used the UIC parameter in the Tran line. I think that applies the trivial DC operating point to all the nodes. I think it's something to do with the time step in the tran simulation is there anyway to check this ?
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Yes i was updating my answer with this option as well!
Another way to speed up simulation is to avoid too steep voltage changes in your voltage/current sources, and of course the timestep set in the .tran matters too,
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I see got it.
Is there anyway to track maybe on how many iterations are pending I'm not too well versed with the internals of ngspice this might not even be possible. Just wanted to check