Confusion over KiCad libraries and moving from Eagle - Page 1
Forum section: electronics / general

author: Northy
author_rank: Regular Contributor
timestamp: June 17, 2025, 01:53:55 pm
content: Hi,I've done lots of reading but I'm still confused how KiCad symbols and footprints work, there doesn't seem to be a 'part' as such.Is someone able to explain it to me like I'm 5 please?The reason I really want to understand it is that I'm looking at moving over from Eagle and I have extensive custom libraries. My libraries are set up so that each different part is it's own unique thing, with a symbol, footprint and many attributes including manufacturer part number, supplier, supplier part number and anything else useful. This is even down to a 4k7 0603 being a different part to a 10k 0603. By setting it up like this I can easily export a CSV that I can use to create a very detailed BOM.I'd rather not loose all the attributes and would prefer to set up custom KiCad libraries in a similar way if it's at all possible. I've read about using a database, but I'm not really sure how to do it.Has anyone else done anything similar when moving across to KiCad and could help me out please?Thanks,G

author: Doctorandus_P
author_rank: Super Contributor
timestamp: June 17, 2025, 03:52:45 pm
content: Historically, KiCad used very simple libraries. Symbols and Footprints were just separate libraries and you had to make the connection yourself as a part of the schematic creation. This has it's advantages, as you can use an ad-hock "back of an envelope" style to quickly make a draft of a schematic for an idea without having to bother with pesky details. Unlike eagle, in KiCad you can just place a simple resistor, edit it's value field and put some text there. The first project I attempted in eagle did not have a 200mOhm shunt resistor, while I had it lying on my desk. That was an annoyance and disruption of my creative process at that moment.But this approach is also quite limited, so quite early on, KiCad started saving links to footprints in the symbols, and in the library symbols. These days many symbols already have pre-defined links to footprints. But it's still based on the old way, as every symbol just has a simple text string that links to a footprint. If a certain IC (such as the Atmel AVR's have a different pinout, depending on their package, then this results in duplication of the whole symbol in the library. This is an inefficiency, but the translation has to be somewhere, and adding an extra redirection step between symbols and footprints also has it's disadvantages.Both these methods are very simple and straight forward.Recently (I think in KiCad V7) the ability to use database based libraries has been added to KiCad. KiCad only provides an interface to an external database. KiCad does not have any database driven libraries as defaults. This makes it a bit complex to get started (you need to have some database knowledge), but it is also very flexible. Many people have attached their existing database (from another PCB design program) to KiCad, including all in-house attributes etc, and then they can use anything in the database in their KiCad projects.You probably want to use this third way. I don't know if eagle has a real database, or only some internal database, but if you can export as CSV, then you probably have your data in a form that can be read by a database. But again, (I repeat) There is no database integrated in KiCad. You won't find it by clicking around. You have to read manuals, do a bit of studying and set up the database yourself. There are some examples / tutorials of how to integrate such a database on the KiCad users forum.https://forum.kicad.info/

author: langwadt
author_rank: Super Contributor
timestamp: June 17, 2025, 04:07:51 pm
content: Quote from: Northy on June 17, 2025, 01:53:55 pmhere a library with all the basic and prefered jlcpcb partshttps://github.com/CDFER/JLCPCB-Kicad-Librarythat does it the same way,every part has value, symbol,description, footprint, 3d model, datasheet, LCSC number