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Spice Netlist Modification

 

I am a new user of Kicad and so far I have been very impressed. Good 
job to Jean-Pierre for a nice package.

After trying the Spice netlist option, I was left wishing there were 
some more options in building the spice line for each component. As 
it stands now, the spice line is basically REFDES <nodes> VALUE.  
This has some limitations when you want to add more to the spice 
line and not change the VALUE displayed in the schematic.

For example, if I had a transistor that had a VALUE of 2N2222, the 
spice line would display as follows: Q1 1 2 3 2N2222. This would be 
fine if my model name was the same as the VALUE. If the model name 
was something like QMOD_2N2222, this wouldn't work.

Another example would be the case of adding a model to a passive 
component like a resistor. To do this in Spice you need to add the 
model name after the resistance value. A 10K resistor would display 
as follows: R1 1 2 10K. To add the model it would need to be: R1 1 2 
10K RMOD.

Although I am not a software coder, I made an attempt to fix this 
using some of the additional fields available for the components. My 
suggestion is to add a couple of Spice value fields that the user 
can populate and they will only display in the spice netlist. I set 
up FIELD7 to be used to completely replace the VALUE in the spice 
netlist. I used FIELD8 to add additonal text after the VALUE on the 
same line. If both fields are empty, the netlist will default to the 
original line.

I made changes to NETFORM.CPP which I will rename as NETFORM_A.CPP 
and post in the files section. The function I modified is called 
WriteNetListPspice. If anyone else thinks this is a good idea maybe 
it could be added to the program. Since I am not very good with 
software, maybe someone could clean this up and make it better.

Brad








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