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Designing my first PCB. The switching IC in my DC/DC converter requires an exposed pad to be connected to ground to provide a low-resistance path. However, EAGLE wants to leave a clearance between my ground plane and the exposed pad:

My PCB without connection between ground plane and exposed pad.

Is there any way to remove that empty space? I have already tried

  • Setting DRC > Clearance > Same Signals > SMD and SMD to 0mil (nothing happens)
  • Inserting a rectangle on the top copper layer to cover the empty area (the clearance comes back when I reload the board file or press Ratsnest)

Thanks!

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    \$\begingroup\$ The 10uF capacitors have connected to the copper pour, but the thermal pad haven't. That's odd. Could you post your schematic? Also, if you upload your Eagle files somewhere and post a link, I can take a look at them in Eagle. \$\endgroup\$ – Nick Alexeev Jan 27 '13 at 2:17
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Set the Net value of the plane to the same as the Net value of the ground. It'll merge them all together, then.

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  • \$\begingroup\$ Can't believe I didn't see this. (The exposed pad was labeled as "12" not "AGND" in the schematic from the library.) Thanks for your help! \$\endgroup\$ – Kevin Chen Jan 27 '13 at 2:48
  • \$\begingroup\$ The pad would be labelled 12 or PAD or what have you in the footprint and symbol. You should connect it to AGND in the schematic. This is useful because sometimes you may want to use AGND and sometimes some other ground. I know the hidden supply pins in symbols seems to be a more impressive standard, but personally I find it very unmaintainable. \$\endgroup\$ – Chintalagiri Shashank Jan 27 '13 at 7:13

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