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Ground plane problem with pic24fj128ga010

Former Member

image

 

Gee, I know that this hasn't been answered several different ways, but I'm about to pull my hair out after looking around for a while....

 

Eagle 6.40 light and pic24fj128ga010 part.

 

Simply putting ONLY this part into a schematic, I pull up the board (create from schematic).  It's obvious the Vss and Vdd connections are in place already.

 

However, I want to add a ground plane at this point.  I go to the polygon, add it in.... say middle area.  I set it to hatch and rightclick ratsnest.  Nice and neat it pops up.  However, I want to connect this to Vss (the ground pins on the pic24).  So, I rightclick the polygon and rename it to Vss.

 

Boom, the border of the polygon goes back to just dotted and no matter what, the autorouter pretty much just ignores that the polygon is there.

 

I've tried renaming the Vss signal to GND and the polygon to GND.  No luck.  When the polygon is the same name as the Vss signals (whatever it's set to) the polygon just turns to the dashed outline.

 

Any help would be appreciated.  I'm not exactly a NEW NEWBIE, but just haven't cut my teeth on Eagle enough.  I've thrown some basic circuits together no problem but it's time to grow a little...

 

Thanks in advance!

 

Keith

  • 0

    Wouldn't you know it, some "related topics" popped up next to my post after posting.

     

    Correct me if I'm wrong, but I need to drop a via in place with the same name as the ground plane?  I had just assumed that the autorouter would have picked up that the plane was available.

     

    So, when I did add the via, all of a sudden my grids popped back up and it looked like things connected back up.

     

    If this is the correct solution, thanks for your patience and I'll close out this question....

     

     

    Keithimage

  • 0 in reply to Former Member

    On 24/03/13 02:09, krobine wrote:

     

    Correct me if I'm wrong, but I need to drop a via in place with the same

    name as the ground plane?  I had just assumed that the autorouter would

    have picked up that the plane was available.

     

    First, the polygon is not handled by the autorouter. You get the polygon

    even if you don't have the autorouter.

     

    No, you don't need a via. All you need is a bit of already-placed copper

    for that signal on the same board layer as the polygon. Is the PIC

    you're using a DIP or is it SMD? If the latter, was it on the same side

    of the board as the polygon?

     

        TQFP on top, polygon on layer 1 - should work

        TQFP on bottom, polygon on layer 16 - should work

        DIP on either side, polygon on any layer - should work

     

    but:

        TQFP on top, polygon on layer 16 - needs a via

        TQFP on either side, polygon on layer 2 - needs a via

     

  • 0 in reply to autodeskguest

    It WAS TQFP on top, polygon on layer 16....which needed a via.

     

    Thanks for the sanity check!