C5621 and C33 User Guide
1/1553-KRD 131 24 Uen Rev D 2011-11-22
Ericsson AB 2011
12 (37)
Ericsson Confidential
Some of the recommendations provided in this chapter are general PCB
design guideline that may be referred from standard texts concerning the
subject.
4.1
Recommended PCB Footprint
The solder lands of the host PCB should be a mirror image of the 277
Ø
≥
0.63 mm solder lands on the component and preferably not routed on the
outer Cu-layer. The pitch is 1.27 mm. Via-in-pad should be Cu-filled (i.e. solid
Cu-microvia).
To improve flux outgassing during reflow, the Solder Mask Opening (SMO) is
recommended to extend 50 µm outside the package outline on all four sides.
Figure 1, Ø 0.63 mm solder lands with one large solder mask opening
extending at least 50
μ
m outside the package outline on all four
sides
Host PCB Solder Mask
Solder Mask Opening
29.2 mm
29.2 mm
