Ublox SARA-G450 Series User Manual

SARA-G450 - System integration manual
UBX-18046432 - R08 Handling and soldering Page 120 of 143
C1-Public
Cooling phase
A controlled cooling avoids negative metallurgical effects of the solder (solder becomes more brittle)
and possible mechanical tensions in the products. Controlled cooling helps to achieve bright solder
fillets with a good shape and low contact angle.
 Temperature fall rate: max 4 °C/s
☞ To avoid falling off, modules should be placed on the topside of the motherboard during soldering.
The soldering temperature profile chosen at the factory depends on additional external factors, such
as choice of soldering paste, size, thickness and properties of the base board, etc.
⚠ Exceeding the maximum soldering temperature or the maximum liquidus time limit in the
recommended soldering profile may permanently damage the module.
Preheat Heating Cooling
[°C]
Peak Temp. 245°C
[°C]
250 250
Liquidus Temperature
217 217
200 200
40 - 60 s
End Temp.
max 4°C/s
150 - 200°C
150 150
max 3°C/s
60 - 120 s
100 Typical Leadfree 100
Soldering Profile
50 50
Elapsed time [s]
Figure 74: Recommended soldering profile
☞ SARA-G450 modules must not be soldered with a damp heat process.
3.3.3 Optical inspection
After soldering the module, inspect it optically to verify that it is properly aligned and centered.
3.3.4 Cleaning
Cleaning the soldered modules is not recommended. Residues underneath the modules cannot be
easily removed with a washing process.
 Cleaning with water will lead to capillary effects where water is absorbed in the gap between the
baseboard and the module. The combination of residues of soldering flux and encapsulated water
leads to short circuits or resistor-like interconnections between neighboring pads. Water will also
damage the sticker and the ink-jet printed text.
 Cleaning with alcohol or other organic solvents can result in soldering flux residues flooding into
the two housings, areas that are not accessible for post-wash inspections. The solvent will also
damage the sticker and the ink-jet printed text.
 Ultrasonic cleaning will permanently damage the module, in particular the quartz oscillators.
For best results, use a “no clean” soldering paste and eliminate the cleaning step after the soldering.

Ublox SARA-G450 Series Specifications

General

Brand	Ublox
Model	SARA-G450 Series
Category	GSM/GPRS Modules
Language	English