I have been always using bridges with vias. I gues that doesnt hurt but recently I though is it really necessary?

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I know that they're purpose is for the soldering process to be easier, otherwise it would be very hard to heat up the ground plane. But with vias, nothing is being soldered to them, they only connect layers. My question is, should one use bridges for GND vias? I would appreciate all help.


They are called thermal reliefs. You don't need them in vias, and leaving them out should slightly reduce the impedance.

However, if you decide later to solder a test point or whatever into a via connecting to a big and thick ground plane, you may have issues.

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    \$\begingroup\$ I wasnt shure how they are called in english. You are right that sometimes you solder stuff to the vias, especialy when prototyping. I was just wondering either the thermal reliefs serve any additional purpose I wasnt aware of when it comes to vias. \$\endgroup\$ – Łukasz Przeniosło Apr 16 '16 at 8:10
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    \$\begingroup\$ No, thermal reliefs only help soldering something. However vias are not intended for soldering anything. They are covered by solder mask in many designs. And they are very small in modern PCBs. So I suggest never use thermal reliefs on vias. \$\endgroup\$ – Master Apr 16 '16 at 8:54
  • \$\begingroup\$ Use of thermal reliefs depends on soldering technology. If you solder >90% of components by Reflow process - you may need reliefs on BGA pads only. And on testpoints intended for soldering wires. \$\endgroup\$ – Master Apr 16 '16 at 8:56
  • \$\begingroup\$ @Master thermal relief is still required for many smd reflow components to prevent tombstoning and dragging the component out of alignment due to uneven copper weights. I see this happen regularly! \$\endgroup\$ – Loganf Apr 16 '16 at 9:11
  • \$\begingroup\$ @loganf, I wonder what kind of reflow oven did you use? I did not see such problems. I was using either industrial reflow machines with transporter and precise temperature control by zones or small (desktop) machines. The whole cycle time was more than 30 minutes in both cases. \$\endgroup\$ – Master Apr 16 '16 at 10:28

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