4.4mm PCB with blind vias and countersink holes
This is a VERY special 4 Layer PCB with thickness 4.4mm, and blind vias from L1-L2,L3-L4.
Countersink holes :top hole size 1.0mm, bottom hole size 1.6mm min hole is only 0.3mm
Matt Black solder mask. via in pad.
We can make nearly all types of special PCBs,top thermal conductivity PCBs,HDI ,RF,Rigid-flex PCBs. We do what others are unable to do .
Here is the stackup:
PP FR4 bare core 3.065mm
Here is the countersink holes.