Kicad Spice Questions

Software
#1

I’m learning how to use spice in Kicad.
As I understand it Kicad uses ngspice by default… right?

Question 1: When looking at the Sim Parameters Dialog I see a “Compatibility Mode” drop-down menu …
Does this mean I can tell Kicad to use LTSpice instead of NGSpice?

Question 2 - What folder has the Kicad’s NGSpice Model files?
For instance, where is the model file that defines the LM741 OpAmp?

I’ve been Googling, reading, and watching videos for a couple of days now but still have a ways to go so thanks for any kind assistance. I’m sure I’ll have a few additional post on this to get me over the hump.

Thanks for any help.

My system: Windows 10 Pro 64-bit
I’m using Kicad 6.0 but also have 6.99 installed.

#2

Yes, KiCad uses ngSpice.
The ngSpice website on sourceforge is a good place to get more information (inclusive the official ngSpice manual).

No, there are no libraries with spice models (except from the built in sources and passives) delivered as part of KiCad, you have to cobble them together form the internet.
There is a collection of examples on this forum here:

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#3

The compatibility mode is to help with ngspice interpreting models and netlists that are in different SPICE dialects. For more information, see the ngspice manual, section 16.14 (pdf link)

If you want to use a different simulator, you’d have to export a spice netlist (schematic editor File → Export → Netlist and choose the spice tab) and import that into your simulator of choice. Your mileage may vary.

I’d recommend this page on getting started with KiCad & ngspice: KiCad Eeschema as GUI for ngspice, tutorial for setting up the simulation

Holger (ngspice maintainer) is also pretty active on this forum and is extremely helpful.

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