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Need devices with multiple packages

e14 Contributor

My company has designed boards in EAGLE for years, and it's worked well for us.  However, this year, we had a problem with EAGLE and a composite part that caused a run of boards to be populated incorrectly.  Cadsoft support suggested we post a feature request here to resolve this issue and help us avoid rework costs in the future.

 

ISSUE:

We noticed the issue when a board we designed came back from the manufacturer with all parts populated except for two 50-pin header sockets.  Looking further, we noticed that while these parts had a footprint in the layout, they were not listed in the BOM, which we had taken directly from EAGLE.  Their absence from EAGLEs BOM had to do with a mechanical constraint that we needed to place on them.

 

EXPLANATION:

Now these two 50-pin header sockets, J1 and J2, needed to be precisely spaced in order to seat a daughterboard with mating connectors.  Our board designer, a Mechanical Engineer, noticed after precisely placing J1 and J2 that one of them could be moved anywhere in the layout, destroying their mechanical compatibility with the daughter board.  In order to constrain them to the proper spacing and ensure that they'd always move as a pair, he created a custom device in our library with both of their footprints properly aligned and spaced.  Now the daughterboard's mechanical interface cannot be broken by an inadvertent drag-and-drop or by the autorouter.

 

The only trouble with this custom part, however, is that EAGLE does not support composite devices (a device that is placed like one package on the layout, but is really two devices on the BOM) and therefore our custom part could not correctly update the BOM.  However, EAGLE could resolve this by supporting one of both of the following features:

 

RESOLUTION:

Support for composite devices in libraries.  This would be comprised of any two or more library devices on the schematic -- and their packages on the layout -- with the packages being physically constrained to a fixed spacing.

 

Another solution would be if we could group individual packages on the layout so that when any package in the group was moved (via drag-and-drop or the auto-router) the other packages would move with it.  The important part here is that the packages don't need to be locked to the board--they just need to be locked in relative position to the other packages in a group.

 

Both of these solutions would keep EAGLEs BOM accurate without permitting a violation of any mechanical specifications.

 

Thanks for your time!  We look forward to seeing future improvements to EAGLE!

  • in reply to rstefan

    Stefan Richter wrote:

     

    I'm pretty new to Eagle and I'm wondering how to even create a custom

    device with multiple existing packages contained within it. I'd like

    to create a device containing pads for two different Samtec headers in

    order to connect to a daughter board. Much like you, I need them to

    maintain the appropriate spacing as I move the sub-board around my

    main board.

     

    I've seen many tutorials about manually creating and positioning the

    pads, but I'm curious if it's possible to combine the existing

    packages for the Samtecs I need into one device? So far I have copied

    the two Samtec devices into a new library and attempted to edit the

    packages but found no options for adding other existing packages to a

    device.

     

    You need to create your own package for your daugter board.

     

    But if you have have the packages for the Samtec connectors, you can

    create it by copying the packages together.

     

    open the Samtec package, display all layers, group all and copy.

    Then open the package of your daughter board and paste to the

    appropriate location (you can run two instances of eagle in parallel,

    no need to switching between libraries).

    --

     

    Lorenz

     

  • in reply to rstefan

    Hi,

     

    If you already have the package in your library and you want to add a new footprint (for example, one with larger pads) you just need to go to "Device" and add a "New" package.

     

    Then you need to connect each pin from the symbol with the correspondent pad.

  • Hello,

     

    I know this thread is old but it's very relevant to the issue I'm having.

     

    I'm pretty new to Eagle and I'm wondering how to even create a custom device with multiple existing packages contained within it. I'd like to create a device containing pads for two different Samtec headers in order to connect to a daughter board. Much like you, I need them to maintain the appropriate spacing as I move the sub-board around my main board.

     

    I've seen many tutorials about manually creating and positioning the pads, but I'm curious if it's possible to combine the existing packages for the Samtecs I need into one device? So far I have copied the two Samtec devices into a new library and attempted to edit the packages but found no options for adding other existing packages to a device.

     

    When you guys created this device with the two 50 pin headers, did you do so from existing packages or did you have to manually place the pads? Or were you able to just copy and paste the same footprint within the same device since it was an exact duplicate?

     

    Thanks,

    Stefan

  • Also, I meant to say, the suggestion for being able to create a permanent

    "locked together" group and move components in that group relative to each

    other in layout should be an actual thing whether it's done for this

    particular use case or not. It would be useful for many things so I support

    that as a suggestion.

     

    Best Regards,

     

    Rachael

    --

    Web access to CadSoft support forums at www.eaglecentral.ca.  Where the CadSoft EAGLE community meets.

     

  • Also, I meant to say, the suggestion for being able to create a permanent

    "locked together" group and move components in that group relative to each

    other in layout should be an actual thing whether it's done for this

    particular use case or not. It would be useful for many things so I support

    that as a suggestion.

     

    Best Regards,

     

    Rachael

    --

    Web access to CadSoft support forums at www.eaglecentral.ca.  Where the CadSoft EAGLE community meets.

     

  • in reply to autodeskguest

    I have to ask, why did the boards actually come back without the parts

    fitted? Any good CM would have contacted you with a query which you would

    have answered and your board would have been correctly populated. I suggest

    you should think long and hard about if your current CM is giving you an

    adequate service....

     

    On my BOM's I list ALL part and have them marked as fitted or not fitted so

    there is no doubt as to my intentions. Then any pads on the board that

    don't have a corresponding line in the BOM, whether fitted or not are an

    issue that needs to be addressed.

     

    For me, all my parts have a unique in house part number which then maps to

    either a manufacturers part number or a sub-BOM so if there was a case

    where I needed to create a composite component it would have a unique part

    number which would call up it's own sub-BOM with all the parts it

    contained. My system, once finished will roll these parts into the main BOM

    automatically.

     

    Best Regards,

     

    Rachael

    --

    Web access to CadSoft support forums at www.eaglecentral.ca.  Where the CadSoft EAGLE community meets.

     

  • in reply to autodeskguest

    I have to ask, why did the boards actually come back without the parts

    fitted? Any good CM would have contacted you with a query which you would

    have answered and your board would have been correctly populated. I suggest

    you should think long and hard about if your current CM is giving you an

    adequate service....

     

    On my BOM's I list ALL part and have them marked as fitted or not fitted so

    there is no doubt as to my intentions. Then any pads on the board that

    don't have a corresponding line in the BOM, whether fitted or not are an

    issue that needs to be addressed.

     

    For me, all my parts have a unique in house part number which then maps to

    either a manufacturers part number or a sub-BOM so if there was a case

    where I needed to create a composite component it would have a unique part

    number which would call up it's own sub-BOM with all the parts it

    contained. My system, once finished will roll these parts into the main BOM

    automatically.

     

    Best Regards,

     

    Rachael

    --

    Web access to CadSoft support forums at www.eaglecentral.ca.  Where the CadSoft EAGLE community meets.

     

  • in reply to autodeskguest

    I have to ask, why did the boards actually come back without the parts

    fitted? Any good CM would have contacted you with a query which you would

    have answered and your board would have been correctly populated. I suggest

    you should think long and hard about if your current CM is giving you an

    adequate service....

     

    On my BOM's I list ALL part and have them marked as fitted or not fitted so

    there is no doubt as to my intentions. Then any pads on the board that

    don't have a corresponding line in the BOM, whether fitted or not are an

    issue that needs to be addressed.

     

    For me, all my parts have a unique in house part number which then maps to

    either a manufacturers part number or a sub-BOM so if there was a case

    where I needed to create a composite component it would have a unique part

    number which would call up it's own sub-BOM with all the parts it

    contained. My system, once finished will roll these parts into the main BOM

    automatically.

     

    Best Regards,

     

    Rachael

    --

    Web access to CadSoft support forums at www.eaglecentral.ca.  Where the CadSoft EAGLE community meets.

     

  • in reply to autodeskguest

    Morten Leikvoll schrieb:

     

    We could also ask the rhetoric question:

     

    Whats best for your project between:

     

    1-The manufacturers finds an issue with pick and place files that doesnt

    seem to match the board, and contacts you about this.

     

    vs

     

    2-You find that your soc doesnt fit after the board is manufactured.

     

    That's exactly the point here.

     

    Tilmann

     

  • in reply to autodeskguest

    On 25.05.2016 14:57, Tilmann Reh wrote:

    Marius Aabel schrieb:

     

    When the board is sent to manufacturing, the pick and place is not going

    to mount one single component, but two header plugs. For the PCB

    manufacturer, this is not one component, it is two. The BOM would have

    to be manually edited instead of using automatic integrations to Eagle.

     

    So, what I am probably going to do, is make the module into two

    components, each with one header. It is more important for me to keep

    the PCB correct, than the schematic.

     

    However, take care that with your method you get the maximum chance to

    make your board completely invalid, by putting the two connectors (and

    eventually additional mechanical things like centering or mounting

    holes) in the wrong relation to each other.

     

    For me, it is also most important to keep the PCB correct, and that's

    exactly why I use a single package in such cases.

     

    Manually editing the BOM for P&P appears as the much better way to go...

     

    We could also ask the rhetoric question:

     

    Whats best for your project between:

     

    1-The manufacturers finds an issue with pick and place files that doesnt

    seem to match the board, and contacts you about this.

     

    vs

     

    2-You find that your soc doesnt fit after the board is manufactured.