QS8M
Layout Guidelines
Land pattern
See figure above for the suggested module layout. The five
1mm pads in the square GND pad cutout can be omitted if
no JTAG Boundary Scan test is used. The solder mask
openings are shown below.
The ground pad solder mask on the bottom side of the
QSCOM module is divided into sections for a better reliability
of the solder joint and self-alignment of the component.
If the via holes used on the application board have a
diameter larger than 0.3 mm, it is recommended to mask
the via holes to prevent solder wicking through the via
holes. Solders have a habit of filling holes and leaving voids
in the thermal pad solder junction, as well as forming solder
balls on the other side of the application board which can in
some cases be problematic. The 0.7mm wide solder mask
stripes can be used to arrange the vias as shown here:
Ka-Ro electronics GmbH - Pascalstr. 22, D-52076 Aachen, Germany - Tel.: +49 2408 1402-0 (FAX -10)
www.karo-electronics.de
