topic Re: Pads different when library part is brought into a design. in EAGLE Forum

Pads different when library part is brought into a design.

grahamUTKMN — Mon, 26 Oct 2020 16:40:33 GMT

I've drawn up a hybrid USB-C connector (SM and TH) to use in my current design.

The pin holes are 0.4mm and the pad diameter is 0.6mm as per the manufacturer datasheet.

When I bring the part into my design the pads on the pins all overlap and I get errors.

What's going on here?

The connector is this one:

https://www.cuidevices.com/product/interconnect/connectors/usb-connectors/uj31-ch-g1-smt-tr

https://www.cuidevices.com/product/resource/uj31-ch-g1-smt-tr.pdf

Thanks,

Re: Pads different when library part is brought into a design.

one-of-the-robs — Mon, 26 Oct 2020 19:00:11 GMT

https://forums.autodesk.com/t5/eagle-forum/frequently-asked-questions-for-autodesk-eagle/td-p/8912704

https://forums.autodesk.com/t5/eagle-forum/9-4-different-pad-sizes-in-library-footprint-and-pcb/m-p/8998434

https://forums.autodesk.com/t5/eagle-forum/custom-part-footprint-error-pad-overlapping/m-p/8666322

https://forums.autodesk.com/t5/eagle-forum/package-in-library-different-from-in-board/m-p/7840312

https://forums.autodesk.com/t5/eagle-forum/component-pad-changes-when-adding-to-a-board/m-p/9745985

https://forums.autodesk.com/t5/eagle-forum/mismatch-between-library-and-footprint/m-p/9676204

... and many more

Is it really that hard for people to find any of those previous posts, especially when the first one IS THE FORUM FAQ

Re: Pads different when library part is brought into a design.

grahamUTKMN — Tue, 27 Oct 2020 10:02:52 GMT

OK, yeah, maybe I could have found that 😥

I'm not used to the software basically over-ruling what I've drawn in the footprint, but now I know I know I guess 😊

What is the best strategy to fix this then? My pads in the footprint are not set to auto.

Thanks,

Re: Pads different when library part is brought into a design.

one-of-the-robs — Tue, 27 Oct 2020 13:41:44 GMT

You need to set your design rules to reflect the capabilities of your chosen fabricator. Essentially, you're telling Eagle (in the DRC) that it's not possible to reliably make PTH pads with thin enough rings for the pin spacing. If that's true then you've got a serious problem. If it's not, then change your DRC settings to tell the actual truth and all should be well.

It does confuse people that the DRC rules override the library pad size even when it's not "AUTO" but that's just how it works. The library setting is effectively saying "I want at least this, even if I could fabricate it with less".

Re: Pads different when library part is brought into a design.

grahamUTKMN — Tue, 27 Oct 2020 16:45:22 GMT

OK, thanks. I've tweaked the rules for our board manufacturer, it's never been a problem up until now.

I guess I'll also have to check that all components with PTH pads have the pad size set manually in the library and not set to auto.

Thanks,

Re: Pads different when library part is brought into a design.

john_norton360 — Fri, 24 May 2024 13:24:48 GMT

This is an awful feature. For sure it's fine for the DRC to flag the problem but for the DRC to automatically modify the copper is just plain the wrong way to do it...!

Just wasted another hour trying to workout why I had a discrepancy between the library and the design.

Re: Pads different when library part is brought into a design.

jorge_garcia — Fri, 24 May 2024 20:06:41 GMT

Hi @john_norton360,

I hope this message finds you well. We are currently working a new DRC dialog and re-visiting it's behavior. This is is one of the things we intend to address. Most new users run into this at least once.

Let me know if there's anything else I can do for you.

Best Regards,

Re: Pads different when library part is brought into a design.

grahamUTKMN — Tue, 28 May 2024 08:33:16 GMT

@jorge_garcia

But not in Eagle, in Fusion right?

Eagle is being killed off still?

Re: Pads different when library part is brought into a design.

jorge_garcia — Tue, 28 May 2024 19:19:46 GMT

Hi @grahamUTKMN,

This change will be coming to Fusion, it will not be in EAGLE. As you have correctly stated EAGLE will be EOL of June 7,2026.

Let me know if there's anything else I can do for you.

Best Regards,