Errors in waveform file notice

Press the pink Ot (output file) button, for those in black and white, its left and down a bit from the blue IE button. If this file is blank then the analysis setup or circuit schematic is incorrect in some manner. Do not put voltage sources or inductors in parallel, or current sources in series, you will generate sparks and get your bottom smacked.

There is also a Spice engine logging file that may contain useful error messages. Press the pink 'Lg' button for this. Not all xspice messages are logged.

Make sure that there is at one ground/earth on the schematic.

Convergence:

Failure to converge is always a possibility in spice. The most common reason for this is a circuit that cannot actually exist in the real world. Make sure there is at least some resistance and capacitance in the circuit at appropriate places. Infinite voltages, currents and infinitely fast responses are bound to cause problems. Do not have floating nodes. For example, the mid points of series connected capacitors are at undermined potentials. Ideal Spice3 switches are often a problem due the discontinuous nature of its implementation. The XSpice aswitch is an alternative.

If the above checks out, try enabling the gmin stepping and srcstepping by using the relevant spice options in the blue "SS" setup dialog window

Check that all nets connected together have the same name. By mousing over them and viewing their name in the status bar at the bottom of the SuperSpice main window. On rare occasions nets may need to be deleted.

Make sure that the circuit has at least one ground.

Make sure that there is a dc path to ground at all nodes, e.g. the mid point of capacitors.

Make sure that there are no floating nodes, i.e. dc path to ground.!

Make sure that enough resolution is used in transient analysis. i.e. do not set the maximum calculation time to large, but note that too small a value will extend simulation time significantly.

Moving wires after simulation may destroy the node name, thereby preventing node probing on those wires.

And lastly,

Make sure that the circuit has at least one ground!

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