Hello,
I have been avoiding BGAs until now, but it seems that I
can't do avoid them anymore... I'm having some issues that would
need clarifications though, before I even start experimenting.
The BGA I'm considering has following specifications:
Ball pitch 0.8mm
Ball diameter 0.4mm
Ball landing 0.43mm
Solder mask opening 0.3mm
The latter two are somewhat confusing. Does that really
mean that the the diameter of solder mask opening is smaller
than the ball itself, ie, the copper should be partially
covered from edges by the mask? (and follow up if so; "how
that is done?")
Then, somehow I don't feel comfortable using very small (0.1mm)
drills, but guess there is no way to avoid those? Or would it
be better to use larger drill and smaller diameter copper
around it?
