Cinterion BGS3, Hardware Interface Description

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BGS3 Hardware Interface Description
6.2 Mounting BGS3 onto the Application Platform
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BGS3_HD_v01.000d Page 93 of 109 2010-03-26
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6.2 Mounting BGS3 onto the Application Platform
This section describes how to mount BGS3 onto the PCBs (=printed circuit boards), including
land pattern and stencil design, board-level characterization, soldering conditions, durability
and mechanical handling. For more information on issues related to SMT module integration
see also
[9] .
6.2.1 SMT PCB Assembly
6.2.1.1 Land Pattern and Stencil
The land pattern and stencil design as shown in Figure 37 and Figure 38 is based on Cinterion
characterizations for lead-free solder paste on a four-layer test PCB and a 120 micron-thick
stencil.
Taking the copper pad area as base, maximum possible overprinting is 85% of this area. How-
ever, Cinterion tests have shown that for most pads an overprinting of 40% is well suited, i.e.,
1.3mm x 1.3mm. An exception is the RF pad: Because of the smaller distance to the adjacent
ground pads, there should be no overprinting to optimize RF performance.
Figure 38 shows the
recommended stencil design.
Figure 37:
Land pattern (bottom view)