Eagle Part Design Question

[MoltenVoltage]

I'm trying to make a custom through-hole component in Eagle that has pins which are always connected to each other, so I want those permanent connections to be part of the component in the library.

I connect the through hole pads by drawing a wire and putting it on the bottom layer, but when that component is placed on the layout, Eagle does not recognize the fact that the pads are electrically connected.

So I tried connecting pins in the part's schematic symbol by drawing lines between them on the Net layer.

This also fails to create an electrical connection, because when I place the part in the schematic and I try to connect other nets to the line between the pins, it fails to make the connection.

Has anybody else ever tried to create a part like this and figured out how to do it?

Thanks!

[bean]

Hmmm, maybe try changing the wire connecting the pads from the Bottom layer to the Pads layer?

Or, maybe connect the pins to the same net in the schematic portion?

Not sure.

[defaced]

I'm thinking the same as bean, move the wire to the pads layer. 

[Gurner]

Here's how I'd approach it (can't say that it works, but might be worth a pop).

Open your package, change to the pads layer, use the rect tool to 'short' your required pins...



save your package.... try recreating your custom part in the  'device' bit of your library

Can't see why such an approach wouldn't work - as your board view will always end up with whatever your 'package' has been designed in the package editor.

[MoltenVoltage]

I've tried connecting the symbol pins on the pads, net, and bus layers and none of them would work to create an electrical connection that Eagle would recognize when the part is used in the schematic.

I tried drawing the connections in the package on the bottom layer, but i will need to try it on the pads layer.  Maybe that will work.

The part shows up "as drawn" on the layout and in the schematic when placed in the project, the problem is that Eagle fails to recognize the electrical connections for either the part or the package.  If either worked I think my problem would be solved.

Thanks for the feedback.

[defaced]

Ok, got it now.  When you build the package, you tell eagle what pins go to what nets.  You need to fix that link and have both pins linked to the same net.  Assuming you can do that.  Never tried. 

[Gurner]

I've tried connecting the symbol pins on the pads, net, and bus layers and none of them would work to create an electrical connection that Eagle would recognize when the part is used in the schematic.

I tried drawing the connections in the package on the bottom layer, but i will need to try it on the pads layer.  Maybe that will work.

That's the point - in my example, above I've electrically shorting the pads in the *package* view (not the symbol view)....whether eagle thinks they're electrically connected or not - they're definitely electrically connected when you etch the board!

[MoltenVoltage]

I don't think you can connect nets when building a part, you can only connect a pin in the symbol to a pin in the package.  The nets I drew in the symbol were not listed in the connection dialog box when assembling the part (i.e. connecting the symbol to the package).  Maybe I missed something.  I'll take another look.

@ Gurner - You are right that the pins are connected when you etch, the problem is when you hit "auto route", Eagle makes a whole bunch of additional , unnecessary connections since it doesn't acknowledge the ones that are already there.

[bean]

...the problem is when you hit "auto route", Eagle makes a whole bunch of additional , unnecessary connections since it doesn't acknowledge the ones that are already there.

Dude, c'mon. Auto-route? Man up!


*just kidding 



One thing about moving from bottom layer to pad layer: if it's something you are going to have manufactured, could that cause a problem?

[Gurner]

@ Gurner - You are right that the pins are connected when you etch, the problem is when you hit "auto route", Eagle makes a whole bunch of additional , unnecessary connections since it doesn't acknowledge the ones that are already there.

But if you create  the package as I did with the 'shorted pads' , but only 'link' the 'symbol'' pins of interest to one of the package pads in  the 'device' editor (ie disregard the other pad) then Eagle will only know of one pad? (or am I missing something)

(likewise, I don't auroroute!)

[MoltenVoltage]

...the problem is when you hit "auto route", Eagle makes a whole bunch of additional , unnecessary connections since it doesn't acknowledge the ones that are already there.

Dude, c'mon. Auto-route? Man up!


*just kidding 



One thing about moving from bottom layer to pad layer: if it's something you are going to have manufactured, could that cause a problem?

I'm moving to SMT.  Now if you want to man up, either wire point to point or get out your tweezers.