Vias are inductive in nature.
If two vias placed very near then it acts like a transformer which leads more crosstalk and de-rated signal integrity.
so shield is necessary.
Vias are inductive in nature.
If two vias placed very near then it acts like a transformer which leads more crosstalk and de-rated signal integrity.
so shield is necessary.
Vias shielding usually connecting the ground plane, the top and bottom with a lot of vias that surround specific portion of the board, this allow the good current flow the plane and isolate that portion with the rest of the board.
We do via shielding to avoid other signal to disstort from the signals which have shielding vias, because every transmission line have EM lines of fores and these vias absorbs its EM radiations.