JODY-W2 - System integration manual
UBX-18068879 - R14
Design-in
Page 32 of 84
C1 - Public
describes the pin layout for the JODY-W2 series module. The proposed land pattern layout
reflects the pin layout of the module. Both Solder Mask Defined (SMD) and Non Solder Mask Defined
(NSMD) pins can be used, however the following considerations apply:
•
Pins from 1 to 60 should be NSMD
•
Inner pads must have a good thermal bonding to PCB ground planes to help spreading the heat
generated by the module.
•
If NSMD design is chosen for inner pads, thermal reliefs should be considered and 4 or 9 vias per
pad must be added for heat sink. Those vias may require copper capping.
•
If SMD design is chosen for inner pads, the land pattern can be flooded on a ground plane beneath
the module and vias added around the pads for heat sinking.
The suggested stencil layout for the JODY-W2 module is to follow the copper pad layout exactly as
described in
for the outer pads, while the central pads should implement a special solder
paste pattern with the following characteristics:
•
Solder paste area should be split in several smaller parts, typically four to nine depending on
copper pad area.
•
Total solder paste area should cover about 50% to 60% of copper thermal pad area.
•
Total solder paste area must not exceed 65% of copper thermal pad area.
Missing to consider solder paste optimization may lead to poor soldering quality in production.
shows a suggested stencil opening implementation.
Figure 10: Stencil opening example for inner thermal pads (dimensions in
µ
m)
⚠
The exact mask geometries, distances and stencil thicknesses must be adapted to the specific
production process of the customer.
2.8
Thermal guidelines
JODY-W2 series modules have been successfully tested from -40 °C to +85 °C (or -40 °C to +105 °C
for JODY-W263-01A) at an ambient temperature inside the enclosure box. The board will generate
heat during high loads that must be dissipated to sustain the lifetime of the components.
The improvement of thermal dissipation in the module decreases its internal temperature and
consequently increases the long-term reliability of the device for applications operating at high
ambient temperatures.
