[quote userid="748809" url="~/cadence_technology_forums/f/custom-ic-design/63251/viva-xl-graph-result-different-from-schematic-result/1402921"]That said, it means that the value annotated on the schematic and Viva XL Graph values are calculated in different way? Is there any way to know, or make them calculated in the same manner? I mean, I would like my Viva XL Graph provides the same result as in annotated schematic and vice versa.[/quote] First of all, I would be very wary of the scenario where your simulation results are sensitive to the initial conditions - you should investigate whether the circuit is behaving as you expect. Trying to force your circuit to give you one of the operating points is risky - this tends to suggest that your circuit has multiple operating points in real life and so it may not behave the way you expect in the real circuit (detecting whether a circuit has multiple stable operating points in simulation is difficult, by the way). The reason for the difference here is as I explained previously. The DC operating point analysis is run from the parameter values (without the sweep) and so it's probably starting from all nodes being at 0V and converging from there. With the nodeset you gave it a different starting point. With the sweep, each sweep point typically starts converging from the previous solution - because usually this is close to the current solution and should converge more quickly - however, that means that you don't necessarily get the same result. This re-use feature is useful - if you are investigating hysteresis type effects, then the direction of the sweep will give different results (there's a switch in the dc analysis to sweep up then down to observe this). [quote userid="748809" url="~/cadence_technology_forums/f/custom-ic-design/63251/viva-xl-graph-result-different-from-schematic-result/1402922"]So I would like to revise my question. Is there a way we can set the simulator to use every sweep step as a new starting point?[/quote] There is an option swpuseprevic=no which can be added to the dc analysis. It's not on the form in ADE, but you can go to the DC options form and then in the additionalParams field at the bottom of the options form, enter swpuseprevic=no . This still might not give the same results, but it might give you the answers you want (as I said earlier about being careful not to convince yourself that all is rosy when there is probably a genuine issue with your circuit). More details can be seen here: Understanding difference in results when parametric sweep is used with DC sweep w.r.t. standalone DC sweep Andrew
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