Creating new eagle part - multiple pins, same signal?

Community PCB Design
1

I’m relatively new to Eagle and have only taken the SFE Eagle class. I’m trying to create a new part using the directions outlined in Lecture 10 of the SFE embedded electronics series. I’m using Eagle 5.4.0.

My question is this: How do you create part which has multiple pins named the same name?

Specific example: a [Vinculum has multiple GND pins.

In my own example, I’m not using a vinculum but I will have multiple GND pins on the part. When I get to the stage of naming my pins, the 2nd GND pin naming causes Eagle to complain “Name GND already exists!”

My part is really just a connector system and will have multiple GNDs, so it’s similar to the Vinculum example in that regard.

How can you create a part which has multiple pins named the same thing?

Thanks for any help over the learning hump here.](http://www.vinculum.com/documents.html#vdatasheets)

2

In the Symbol editor, name your ground pins “GND@1”, “GND@2”, “GND@3” for example, and change them to “POWER” pins…

That should join all your grounds with airwires when you route ya board. :wink:

Probably not the best way to do it and there must be another way to… But, i can’t think.

3

Thank you for your response. I’d like to get one clarification if you don’t mind. I apologize for needing explicit instructions…I’m still learning this tool.

In my example, in the symbol editor, I’ve drawn my component with the wire tool and I’ve just gone through the process of laying down a bunch of pins on it, say P$1 → P$44.

I start naming these and when I come across a pin for which I know there will be multiples of the same name, GND, for example, I’ll rename P$x to GND@1, P$y to GND@2, P$z to GND@3 and so on.

The part where I lost you was this - I just got through naming them, but you say that after I name them I should “change them to ‘power’ pins.” I’m looking at the “wrench” icon in the new part symbol editor but don’t see a way to change the attribute of the pin to ‘power’.

I’m obviously not understanding. Are you saying in the symbol editor I should just ignore for now the fact that these aren’t “tied” together in any way, but when I use this device in a schematic, give them all net names of GND? I think that’s what you’re saying, but just want to be sure I’m not missing your meaning.

Thanks again.

4

Done good so far… :wink:

You can’t connect any pins together in the symbol editor…

Using the info tool in the Symbol editor, click on the pins and there will be a drop down box labeled “Direction”, change them to “Pwr”.

Later, in the Schematic editor, you won’t need to connect all the pins to ground, just one.

As i said, this way probably isn’t the best way to do this but for one-offs, it’ll work. :lol:

Haha, i have just found what i was talking about in the EAGLE Manual! Cheating i know…

Page 232 if you’re interested.

5

Great answer. Thank you.

6

Just a note as I’ve learned through using Eagle…

When naming power pins, since a lot of power pins also have the same name, name them something like

VCC@X

Where X is the actual pin number for that particular pin. This will help later when you are trying to place filtering capacitors next to the pin you have them at on the schematic. Later you won’t be wondering why your VCC decoupling cap that connects to pin 48 is connected to pin 84 on your board…

7

Good tip, thanks.

8

I’m trying to create library entries for NJM3771 stepper motor drivers. ( http://www.datasheetcatalog.org/datashe … e04006.pdf ) As well as having multiple GND pins the number of GND pins varies between DIL and SMD packages.

I’m using the GND@ convention but am stuck on how to get the library entry to deal with that different number of connected pins.

Any idea’s?

Bob