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Topic: Eagle - Many package connections to one device pin? (Read 2356 times) previous topic - next topic

Marvin Martian

Another Eagle component library question - if you have a package that has several pins all connected internally together (multiple grounds for example) is it possible to connect these all to the same pin in the device / symbol?

The pins to pads connection process seems to be a one to one relationship. I tried renaming the pads to the same name but it won't allow that... is there any other trick?

Cheers

gutbag

I think it's the Append button in the Connect dialog.

CrossRoads

For things like multiple GNDs, I name them GND1, GND2, GND2, etc, and then make sure they are all connected on the schematic.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

Tom Carpenter

Yup. Make one connection as normal, then select each additional pin in turn, pressing append after selecting.
~Tom~

kg4wsv

There's a trick for that; IIRC it involves @ in the name.  e.g. pins GND@1 GND@2 GND@3 are all GND.

Do some googling and you'll find details.

-j

Marvin Martian

Ah yes - append what I needed - screamingly obvious when you know!
Thanks

Marvin Martian

Spoke too soon - the Append isn't quite what I needed since Eagle will still run a ghost wire between the two pads and expect them to be connected with a trace, whereas they are electrically connected on the physical device, so the trace is unnecessary.

I looked at the @ option too but that seems to require a symbol pin for each connected pad. The example I have is a battery holder, so obviously I want a standard 2 pin battery symbol for the circuit...

kg4wsv

Quote
I looked at the @ option too but that seems to require a symbol pin for each connected pad. The example I have is a battery holder, so obviously I want a standard 2 pin battery symbol for the circuit...

I think you call the one on the symbol GND, but it will want all of the GND@X pins connected on the PCB.

You don't have to connect all of the pins to the device, so you can have GND, GND2, and + pins on the package, but only have GND and + on the device.  This would leave you with a permanently isolated pad on the board (so you have mechanical mounting) but no electrical connection.

For example, here's a coin cell battery holder from the Sparkfun eagle library that has a large SMT pad for one side of the battery and two through-holes which are electrically connected on the battery holder, but only one of them is connected in the library device and the results is the electrically isolated through-hole.



Is that what you're after?

-j

Marvin Martian

Not quite - I want to be able to connect to either of the hole pads on a layout by layout basis, and want it to know that they are electrically connected/equivalent without having to connect them myself via PCB traces.

From looking at what Sparkfun have done, I think it's safe to assume I can't.

Chagrin

This is a common Eagle question, and no, it can't be done. Crossroads' advice is the way to go.

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