Diode mixed pin -> incompatible with ngspice

Schematic
1

I Just get the nightly build,and there is still a mix with diode pin, between schematic and net list -> pin are inverted for ngspice syntax.

JP

1 Like
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About a year or so ago KiCad started following IPC rules on pin numbering. This affected diodes at the time. I donā€™t think KiCad will be changing back

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The IPC convention puts the diodeā€™s cathode connection on Pin 1. Check your schematic symbols to confirm that they follow this convention. If they do not, then you should consider re-drafting the symbols, as well as the footprints they refer to.

That could avalanche into a lot of work if there is a long history of using symbols that donā€™t conform to KiCADā€™s current practice. To run SPICE from KiCAD without correcting the symbols, you could try redefining the diode models as Subcircuits, with the anode and cathode connections swapped. I donā€™t know whether KiCADā€™s SPICE interface will allow you to call a subcircuit when the symbol shows a diode. The other alternative is to intercept the netlist which KiCAD passes to SPICE and manually edit the Diode statements.

Dale

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Have you used the ā€˜Alternate node sequenceā€™ option in the spice gui?
For most diodes I set it to ā€œ2,1ā€ to adapt the pin ordering to what ngspice is expecting.

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I have made a summary of the things I found while using ngspice from EEschema.
It is here.

Perhaps this will be helpful.