Huawei MU609 Getting To Know Manual page 7

Design of Solder Mask
The PCB pad design can be solder mask defined (SMD), or non-solder mask defined

(NSMD).NSMD is recommended. In addition, the solder mask of the NSMD pad design
is larger than the pad so the reliability of the solder joint can be improved.
The solder mask must be 100 µm to150 µm larger than the pad, that is, the single side

of the solder mask must be 50 µm to 75 µm larger than the pad. The specific size
depends on the processing capability of the PCB manufacturer.
Assembly
Stencil Design
It is recommended that the stencil for the LGA module be 0.15 mm in thickness. For the
stencil design, see the following figure：
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