topic Re: Overlapping components with AGND & GND polygons in EAGLE Forum

Overlapping components with AGND & GND polygons

usfwalden — Wed, 28 Sep 2022 17:22:46 GMT

Hello and thank you in advance,

Pictures of the 3d model of the circuit board I'm working on are attached.

I've got a row of current sense resistors between two large through hole connections.

The goal is to create matching paths on the top and bottom layers stitched together with vias and apply copper bus plates on both the top and bottom.

To complicate things, I have an AGND pour and a GND pour on the bottom layer which are to join at the Bat- terminal.

The question is: How do I stack these things on top each other efficiently and get Eagle to connect them altogether instead of isolating them?

Initially I created the through hole as a library part with a through hole pad.

Then I created a library part for the top bus plate and another for the bottom bus plates.

The footprints for each of those were a round smd pad + rectangle overlaying half of the smd pad and extending out.

This stacked up as 3 parts, the bottom bus plate, the through hole, and the top bus plate. Each had a single pas pin connected to a bat- net to which I connected both the gnd and agnd supply pins in my schematic.

This arrangement didn't allow either the agnd or gnd pours anywhere near the stackup.

I went back and reworked the through hole part, adding a sup agnd and a sup gnd pin to the symbol and added two smd pads onto of the through hole pad to connect them to. This allowed the ground pours to connect although for some reason the agnd still isolates from the rectangle portion of the bottom bus plate footprint.

I still need to manage the stiching vias and creating a solid pour between the bus plates and the resistors.

My current efforts seem overly complicated.

What's the right way to do this?

Re: Overlapping components with AGND & GND polygons

usfwalden — Wed, 28 Sep 2022 19:44:16 GMT

I started with deleting the bus plate parts to simplify things.

I then tried editing the through hole pad part stacking smt pads with identical dimensions ontop. That didn't work.

Then I deleted the through hole pad part.

This let my GND and AGND polygon pours fill in.

I then layed a Bat- polygon overtop the GND and AGND polygon pours and it successfully bridged the gap.

I added a hole in the milling layer.

I was then able to stitch it all together with vias named Bat-.

With this I should at least be able to successfully get the board fabricated.

The question remaining is how do I add the bus plates to the design so that the 3d assembly is correct?

Re: Overlapping components with AGND & GND polygons

usfwalden — Thu, 29 Sep 2022 00:52:56 GMT

After several different attempts the solution I came up with to re-incorporate my bus plates was to edit the part to unassign the pins and delete the symbol then edit the footprint to only include a stop mask and a place outline.

Anyone with other methods please do share.