Product Info

LTE Module Series
EC21 Hardware Design
EC21_Hardware_Design
8-89
/ 105
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
so as 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 0.20mm. For more details, please refer to
document [4].
It is suggested that the peak reflow temperature is 235ºC~245ºC (for SnAg3.0Cu0.5 alloy). The absolute
maximum reflow temperature is 260ºC. To avoid damage to the module caused by repeated heating, it is
suggested that the module should be mounted after reflow soldering for the other side of PCB has been
completed. Recommended reflow soldering thermal profile is shown below:
Figure 48: Reflow Soldering Thermal Profile
During manufacturing and soldering, or any other processes that may contact the module directly, NEVER
wipe the module label with organic solvents, such as acetone, ethyl alcohol, isopropyl alcohol,
trichloroethylene, etc.
NOTE