User Guide

ME910G1 Preliminary HW Design Guide
1VV0301593 Rev.2 Page 74 of 95 2020-01-13
Recommendations for PCB pad dimensions
It is not recommended to place via or micro-via not covered by solder resist in an area of
0,3 mm around the pads unless it carries the same signal of the pad itself
Holes in pad are allowed only for blind holes and not for through holes.
Recommendations for PCB pad surfaces:
Finish
Layer Thickness (um)
Properties
Electro-less Ni /
Immersion Au
3 –7 / 0.05 – 0.15
good solder ability protection,
high shear force values
The PCB must be able to resist the higher temperatures which are occurring at the lead-
free process. This issue should be discussed with the PCB-supplier. Generally, the
wettability of tin-lead solder paste on the described surface plating is better compared to
lead-free solder paste.
It is not necessary to panel the application’s PCB, however in that case it is suggested to
use milled contours and predrilled board breakouts; scoring or v-cut solutions are not
recommended
Inhibit area for micro-via