Kicad: Blank SOP-8 Symbol + Footprint?  - Page 1
Forum section: electronics / general

author: LooseJunkHater
author_rank: Frequent Contributor
timestamp: September 22, 2023, 08:45:10 pm
content: I'm having trouble finding a simple "template" or blank SOP-8PCB footprintandschematic symbol. All I can find within KiCad is ones that are already populated with writing identifying which pins are VCC, GND, switching, etc.I'd also rather NOT create my own blank templates, as that appears to be quite timeconsuming per the YouTube video that I've watched.

author: ataradov
author_rank: Super Contributor
timestamp: September 22, 2023, 09:05:06 pm
content: Creating a symbol takes virtually no time, especially for 8 pins. But even if you don't want to make a new one, take the existing one and edit the pin names to be generic.And you don't need to make the footprint, since they are already generic.Eventually you will run into something without an existing footprint, and 8-pin device is perfect for practice.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: September 23, 2023, 12:02:33 am
content: Indeed. The only time consuming part is learning how to create and/or modify schematic symbols and footprints. After that, making a custom 8-pin part is done in 5 to 10 minutes.It also looks like you are not very familiar with KiCad yet. PCB footprints are never:"already populated with writing identifying which pins ar VCC, GND, etc".The footprints are always generic and they just have pin numbers. If you see texts on the pins in the PCB editor, then it is the text from the net name given to it by the schematic.Changing the texts of the pins of exisiting schematic symbols is as simple as hovering over a schematic symbol press[Ctrl + e]to load it in the symbol editor, selecting a pin and editing it's pin name. This takes about 10 seconds to do. The only thing that makes it a bit more involved is the library management, and that is improving too with each KiCad version.

author: LooseJunkHater
author_rank: Frequent Contributor
timestamp: September 23, 2023, 01:15:05 am
content: I'm definitely a noob to KiCad. I always go back to Draw.io or Falstad because KiCad overwhelms me but I'd love to create some circuits and share them on Github or Tindie, hence why I want to dedicate more time to learning it.So what I did on the left-side of the screen in "Libraries" is search for "SOP-8", and it only ever shows pre-made IC's. I try to modify the labels and location of pins (see pins 3 is up top and pin 2 is at the bottom) but I can't figure it out. I've tried Googling this information but I can't figure it out.

author: ataradov
author_rank: Super Contributor
timestamp: September 23, 2023, 01:19:27 am
content: SOP-8 is a footprint, you are searching in the symbols. Those are completely separate.So pick something in an 8-pin package (like I2C EEPROM or SPI flash) and use that as a source.The package you see in the light blue text is the default package that would be used. You can change that later when you are creating a schematic. And this one has exposed pad, which is probably not what you want.So, edit the symbol to make it generic and assign whatever footprint you want by editing the symbol properties.

author: LooseJunkHater
author_rank: Frequent Contributor
timestamp: September 23, 2023, 01:49:32 am
content: Quote from: ataradov on September 23, 2023, 01:19:27 amI tried to do all of that; edit an existing "symbol" and associating it with a "footprint" (with MSOP-8_3x3mm_P0.65mm appearing to be exactly what I want) but I can't save it or I'm just trying to save it wrong? Every time I try to save it it says that the library isn't writable.

author: ataradov
author_rank: Super Contributor
timestamp: September 23, 2023, 02:10:22 am
content: Right click on the device name in the list and click Save As. In the dialog make a new library if you don't have one yet and edit the copy in your own library.

author: Anthem
author_rank: Contributor
timestamp: September 30, 2023, 08:11:20 am
content: There is a fabulous program called KiCAD Librarian which makes its so easy to modify existing components and save them to your own separate library. The man who developed it really could do with more recognition. You can change footprint pad size/ spacing and also view the 3D parts in the library. Also there is a compare facility which allows one to superimpose two components footprints to see the difference. Just typing say hole size in the window and it is done.Link to how its done -and if you'd like to download it has a windows installerhttps://www.compuphase.com/electronics/kicadlibrarian_en.htmof you can do a "make install" from its Gitbub repository -https://github.com/compuphase/KiCad-LibrarianI think 2021 was its last version but it still does the job.Why its is not more popular I am not sure.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: September 30, 2023, 01:46:33 pm
content: That KiCad Librarian program probably was a nice program 5 to 7 years ago. However, in the mean time, KiCad has improved so much that it is very likely mostly obsolete. KiCad's own libraries have improved a lot. The SOT-23 used in the example have now pads of the same size for example. Many of KiCad's footprints are script generated, which makes adjustment and uniformity a lot easier for librarians. KiCad V7.99 also has a properties manager in the Footprint Editor. (similar to the properties manager in the PCB editor in Kicad V7), and with that changing properties of multiple pads in a footprint is very similar to what the KiCad Librarian program does.The KiCad Librarian program is also not updated for 5 years, and this may well make it incompatible with newer Kicad versions.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: September 30, 2023, 01:54:01 pm
content: Quote from: LooseJunkHater on September 23, 2023, 01:49:32 amFirst, you started of with a misconception between schematic symbols and footprints. Those are quite different things, and it is important to fully understand this.And about the "Library isn't writable". KiCad's own libraries are indeed write protected, because they are a part of KiCad itself, and they will be updated with newer KiCad versions. Any changes you have made to those libraries will then be overwritten. And to prevent this from happening, all of KiCad's libraries are read-only. The solution is to first make a library of your own (it can be global or project specific) and then copy the parts from the KiCad library to your own library.