Simulations sometimes fail to converge - that is the simulation aborts before completion with one of these messages:
If this happens, select menu
. You will be presented with this dialog box:
This dialog allows to set a number of simulation options that can help simulation convergence. These options sometimes have a penalty, either they slow down the simulation or in some way degrade accuracy. These are described below
Item | Description |
---|---|
Advanced Iteration | This improves convergence with a slight speed loss. Certain types of circuit benefit more strongly than others. |
Tolerances | Setting current tolerance to 1n sometimes fixes convergence problems. You should not increase this setting if your circuit has very small currents |
Slew rate for discontinuous sources | This will onhy have an effect if you use models that contain discontinuous sources. These are common in switching power controllers |
Shunt capacitance | This is often effective especially if the Apply shunt capacitance globally box is checked. However, this option is effectively modifying your circuit so should always be used with care. Note that this option will only benefit transient analysis |
For more information on convergence issues refer to Simulator Reference Manual/Convergence, Accuracy and Performance
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