LM324 does not match

Layout Footprints
1

Adding one LM324 inserts 4 opamp symbols plus one power input.
The inserted symbols does mach the SO14 package, but not the QFN16
Selecting QFN16 would result in a defective circuit:

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I bet there is some clever way this is supposed to be handled, instead of me modifying five symbol elements? This is a very widespread device, so there must be something I am missing.

Please enlighten me on the correct procedure here.

2

A new symbol is required for the (new-ish) QFN16 packaged part. The existing symbol is a derived part, so unfortunately you can’t just right click > Save Copy As. You’ll need to go find the original symbol and copy that one to a personal library and then edit it. Don’t save a copy of the derived symbol into the existing Amplifier_Operational library, as it should be read-only and may be overwritten next time you update KiCad.

3

At the time the symbol was made, this part was only available in DIP, SOIC, and TSSOP packages. The QFN-16 variant is fairly recent (and not even mentioned in the TI LM324 datasheet that the symbol is referenced on). TSV524xIQ4T is an exact match if you want to use a ready-made part.

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4

This is ST’s LM324Q from the looks of things.

If you’re willing to use 3-rd party libraries you can find that symbol in my library - Alternate KiCad Library. It can be downloaded from the PCM, but I’d strongly recommend looking at it’s docummentation first - there are some things about it that are very different from the KiCad’s default library.

5

My procedure is to:

  • use only my own libraries,
  • have footprint attached to each symbol,
  • modify symbols only in library, never at schematic.

So when I want to change 1k into 1k2 I delete one resistor and insert the second (or there is a function to replace symbol with another one).
In case of ICs with different packages I just add to symbol name a letters used by manufacturer to specify package.

6

Thank you all, it was not difficult to figure out with some help. I was mostly surprised that this part was not in the collection, as LM324 is not exactly new, and I’ve been using that footprint for years.
Anyway: is there a easy way to contribute own symbols/footprints to KiCAD ?

7

To contribute to the official libraries, you will need a GitLab account and some ability to use Git. The process would be:

  1. Fork the the kicad-symbols repo KiCad / KiCad Libraries / KiCad Symbols · GitLab
  2. Check out a local copy of your fork
  3. Create a new branch
  4. Adjust your KiCad’s paths to point to your local copy
  5. Create a new symbol, you can derive it from TSV524xIQ4T, fill in the metadata.
  6. Make a commit and push it to your fork
  7. Create a merge request into the parent repository
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