Manufacturing And Soldering - Quectel EG915U-EU Manual

8.2. 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 0.18 mm – 0.20 mm. For more details, please refer to
document [4].[1]
It is suggested that the peak reflow temperature is 238–246 ° C, and the absolute maximum reflow
temperature is 246 ° C. 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)
246
238
220
200
Soak Zone
150
100
Figure 39: Recommended Reflow Soldering Thermal Profile
Table 38: Recommended Thermal Profile Parameters
Factor
Soak Zone
Max slope
Soak time (between A and B: 150
EG915U-EU_Hardware_Design
A
Max slope: 1 to 3°C/s
° C and 200
Reflow Zone
Max slope:
2 to 3°C/s
B
Recommendation
1 to 3 ° C/s
° C) 70 to 120 s
LTE Standard Module Series
Cooling down slope:
C
-1.5 to -3°C/s
D
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