NB-IoT
Module Series
BC660K-GL Hardware Design
BC660K-GL_Hardware_Design 52 / 57
1.
1)
This floor life is only applicable when the environment conforms to
IPC/JEDEC J-STD-033
.
2. To avoid blistering, layer separation and other soldering issues, it is forbidden to expose the
modules to the air for a long time. If the temperature and moisture do not conform to
IPC/JEDEC
J-STD-033
or the relative moisture is over 60 %, it is recommended to start the solder reflow
process within 24 hours after the package is removed. And do not remove the packages of
tremendous modules if they are not ready for soldering.
3. Take the module out of the packaging and put it on high-temperature resistant fixtures before
baking. If shorter baking time is desired, see
IPC/JEDEC J-STD-033
for the baking procedure.
7.2. Manufacturing and Soldering
Push the squeegee to apply the solder paste on the surface of stencil, thus making the paste fill the
stencil openings and then penetrate to the PCB. The force on the squeegee should be adjusted properly
to produce a clean stencil surface on a single pass. To ensure the module soldering quality, the thickness
of stencil for the module is recommended to be 0.15
–0.18 mm. For more details, see
document [5]
.
It is suggested that the peak reflow temperature is 238 °C
to
246 ºC, and the absolute maximum reflow
temperature is 246 ºC. To avoid damage to the module caused by repeated heating, it is strongly
recommended that the module should be mounted after reflow soldering for the other side of PCB has
been completed. The recommended reflow soldering thermal profile (lead-free reflow soldering) and
related parameters are shown below.
Temp. (
°C
)
Reflow Zone
Soak Zone
246
200
220
238
C
D
B
A
150
100
Max slope: 1 to 3
°C
/s
Cooling down slope:
-1.5 to -3
°C
/s
Max slope:
2 to 3
°C
/s
Figure 32: Recommended Reflow Soldering Thermal Profile
NOTES
