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I can accept all you say, but for my limited work I think that creating new libraries is not justified. The point about the opamp is that the EDR won't tell you that you have provided strong positive feedback because you have not noticed that the + input is at the top. An .AC might also not tell you, but a .TRAN would. My projects are now 'kitchen sink' - special test equipment, usually one-off, but when I was in industry, 4000 would be a very modest run. In those days, it was black tape on drafting film.

Yes the pin positions are more common with -ive uppermost, but not
always. 

The EDR cannot detect this because it in NOT an error it's just how the
symbol was drawn. It's down to the designer to connect the components to
the correct pin.

If you don't like it, then change the symbol...
I can't stand the American electrolytic symbol, so I change that to the
one that I've used for decades, the filled box for -ive and unfilled for
+ive

This highlights a VERY important point for ANY CAD system be it Kicad,
Eagle,  Autocad, or any other design tool.

You NEVER use the provided symbols for live work. You ONLY use symbols
that you have checked and verified as good. These you save in your own
libraries and that's what you use when building your design on the
screen. It protects you from an unknown change being distributed to the
system that you don't spot, so when you use the part again you get
something different.

Not a problem on a single board "kitchen sink" project you just curse at
it, and bodge it. But if that happens on your 4000 board production run
you might be looking for a new job :-)

When you think about it, you only use a very small handful of components
in amateur projects so it does not take long to build up your own
libraries, and most of the provided ones will be perfectly OK so it's
just a matter of copying therm across to your own libs.


Andy



On Fri, 21 Jun 2024 16:04:18 +0100
"John Woodgate" <jmw@...> wrote:

As I understand it, I have to make a copy of the schematic and add 
voltage sources (power and signal) and a load. Then add to that the 
simulation command. But how do I introduce the models and subcircuits 
for the active components?

What would be much easier for me is to be able to copy the schematic 
into LTspice (as that is what I use) and do the simulation in that 
environment. But is is possible to do that, i.e. can KiCad export a 
schematic (or even a netlist) that SPICE understands?

This is important because it can be a costly mistake not to realise that 
the KiCad opamp symbol has the + input uppermost, whereas it is most 
common, I think, to see the - input uppermost. The EDR can't detect that 
error, of course.

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Signature OOO - Own Opinions Only
Best wishes
John Woodgate, Rayleigh, Essex UK
Keep trying

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