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Before I added a ground plane my ratsnest was showing the needed GND connections which I still needed to make. I added a Ground plane and now they are automatically gone. Is this normal?

I can remember that in the past I used a VIA to connect certain components to the ground plane, but that doesnt appear to be needed here, why?

I illustrated the old ratsnest with the orange lines drawn on the image. Any other remarks about the design are welcome as well, always eager to learn.

PCB

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  • \$\begingroup\$ That is normal for a part with a plated through hole intersecting the plane. A surface mount part on a different layer would of course not contact the plane, unless you place a via to create a connection. FWIW you could probably get much better power routing by shifting your resistors some. You might also consider bypass caps... \$\endgroup\$ – Chris Stratton Mar 10 '16 at 23:19
  • \$\begingroup\$ Right, will get on the resistors. Good point. Also this circuit is purely DC so no caps needed \$\endgroup\$ – TheAlPaca02 Mar 10 '16 at 23:32
  • \$\begingroup\$ Funny for a "purely DC" circuit to have a "CLK" terminal... That doesn't mean that bypass caps are required, but it's a lot easier to design the board to support them and later decide you don't need to install them. \$\endgroup\$ – Chris Stratton Mar 10 '16 at 23:37
  • \$\begingroup\$ Its just a multiplexing circuit to drive some RGB leds. But it might indeed be good practice to add them in. \$\endgroup\$ – TheAlPaca02 Mar 10 '16 at 23:41
  • \$\begingroup\$ You also have an option for how you want to connect the pads to the pour, by default most components use "thermal relief" (the crossed spokes) you can also select a solid connection and the result would be no spokes or gaps around the pad (just the green via in the middle of the pour) \$\endgroup\$ – crasic Mar 11 '16 at 1:28
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You've added ground plane (copper pour), and rat's nest connections from the pins to the copper pour disappeared. That's intended. That's how it should be.

If you zoom-in on on of the pins that are connected to ground (for example IC1 pin 8), you'll see spokes. That connect the via to the copper pour. The spokes are created by the software, because the pin is connected to the same net as the copper pour.

ground plane connection with thermal relief (spokes)

By the way, every modern layout software behaves in a similar way (not only Eagle).

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  • \$\begingroup\$ Ah yes. I just dug through some other files and it appears that the situation I was talking about with the VIA's involved SMD's instead of through hole components. That explains my doubt. Thanks for the clarification. \$\endgroup\$ – TheAlPaca02 Mar 10 '16 at 23:18

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