eldo_user

Appendix B
Troubleshooting
Most users of any product will from time to time experience problems in its use. This appendix
is intended to provide an easy to use quick reference from which such problems can be
identified and corrected.
Common Netlist Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1453
Tips for Troubleshooting and/or Improving Convergence and Performance . . . . . . . . 1454
Tips for Troubleshooting Performance Bottlenecks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1454
Troubleshooting File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1455
Common Netlist Errors
There are a number of common errors to look out for when producing an input netlist:
• First Line of a File Not the Title.
The first line of a netlist must be the title of the circuit. If part of the circuit description is
found on the first line, it will be ignored. If the first line is a blank, this will be taken as
the title line.
• Correct Usage of the Simulator Accuracy (eps, vntol, reltol).
The simulator accuracy parameters are the most important Eldo parameters—they must
be correctly initialized.
Tip
For more details refer to the Speed and Accuracy chapter.
• Correct Units on Devices.
It is very important to make sure that all the components in the netlist have correct units;
one mistake can have a large effect. An example of this is specifying units of farads
instead of picofarads.
• Missing Model.
Make sure that model definitions are available to the simulator, either directly in the
netlist, or in a referenced library.
• Missing Voltage Sources.
Independent voltage sources defined to have a voltage of 0V may be removed by Eldo
to simplify calculations. If you wish to use a voltage source as a current probe, avoid
Eldo® User's Manual, 15.3 1453