Vias direct connect better than thermal relief ? Ground/Thermal

Question

I am thinking about if there is a positive point on having vias which have a thermal relief connection to their respective planes? I know that for soldering pads it makes sense having less copper. BUT on simple vias, which are there to connect a ground plane on top to the on on bottom, I don't see any pros having those vias with a thermal relief, as there is no soldering on those vias to be done?! I rather see cons having thermal relief as it only increase the electrical resistance between those ground planes.. Same also for having planes which acts as a thermal sink, the thermal relief would only increase thermal resistance. Am I right about this? Would be happy to hear a few thoughts on this

cheers

Answer 1

I fully agree with you. For some pads that are connected to a big copper area, it's good to have the Thermal relief to make them easy to solder. Even more, when they are big pads, like chassis or big GND pads If you don't apply thermal relief you can struggle while soldering them. For vias I always put them as "Direct connect" the the corresponding net, as you said, you are not going to solder the vias, so I think there is no need for adding that relief. With a direct connection between via and plane, you will have lower resistance and hence, lower heat dissipated there and more current can flow through the via.