User Guide

ME310G1 Hardware Design Guide
1VV0301588 Rev. 11 Page 65 of 91 2021-03-16
PCB pad design
Non solder mask defined (NSMD) type is recommended for the solder pads on the PCB.
Figure 19: PCB solder pad recommendations
The recommendation for the PCB pads dimensions are 1:1 with module pads.
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 / 0.03 – 0.15
good solder ability protection, high shear
force values
Table 36 Recommendations for PCB pad surfaces
The PCB must be able to resist the higher temperatures that occur during the lead-free
process. This issue should be discussed with the PCB-supplier. In general, the wettability
of tin-lead solder paste on the described surface plating is better than the lead-free
solder paste.
It is not necessary to panel the application’s PCB, however in that case it is recommended
to use milled contours and pre-drilled board breakouts; scoring or v-cut solutions are
not recommended.
PCB
Copper
Solder Mask
SMD
(Soler Mask Defined)
NSMD
(Non Solder Mask Defined)