I hereby certify that I am not simply asking someone else to design a footprint for me.
This is an auto-generated message that is in place on the “footprints” section of the KiCad.info forum. If I remove it and ask for a footprint to be designed anyway, I understand that I will be subject to forum members telling me to go design my own footprint or referring me to a 3rd party footprint site.
Good day, I see some libraries that I download have multiple footprints for the same IC. These footprints have the same shape, but different sizes. How would I check in Digikey or other IC providers which size footprint I should use based on what they provide? Note: I go to the IC page on Digikey and download its library on ultra librarian. Thanks in advance!
How would I check in Digikey or other IC providers which size footprint I should use based on what they provide?
Use the IC-datasheet to decide which footprint pattern to use. It’s your task as pcb-developer to choose from the available ic-packages and than design/draw/use the correct footprints for the pcb-layout.
regarding the ic footprint download: be careful. There is no warranty that the footprint is correct in all aspects.
In this forum we get regularly questions like “footprint xy downloaded from xyz doesn’t works”. So take the downloaded footprint only as a starting point, always check for correctness (compare with datasheet).
Most IC’s are available in multiple case sizes. So you could easily choose the wrong one if you don’t compare the mfg drawing to the footprint dimensions.
Personally I make a new footprint for each part I use and store it in my personal libraries. While this seems like a lot of work, once you get the hang of footprints they go pretty fast.
In addition, if you have the part before you order the boards I suggest you print out a 1:1 of the board and physically lay the part on the board drawing. This is especially important for relays, switches etc where it is easy to get the footprint upside down.