LEA-6 / NEO-6 / MAX-6 - Hardware Integration Manual
UBX-14054794
Production Information
Product handling
Page 56 of 85
3.2.4
Cleaning
In general, cleaning the populated modules is strongly discouraged. 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.
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.
The best approach is to use a "no clean" soldering paste and eliminate the cleaning step after the soldering.
3.2.5
Repeated reflow soldering
Only single reflow soldering processes are recommended for boards populated with u-blox 6 modules. u-blox 6
modules should not be submitted to two reflow cycles on a board populated with components on both sides in
order to avoid upside down orientation during the second reflow cycle. In this case the module should always be
placed on that side of the board which is submitted into the last reflow cycle. The reason for this (besides others)
is the risk of the module falling off due to the significantly higher weight in relation to other components.
Two reflow cycles can be considered by excluding the above described upside down scenario and taking into
account the rework conditions described in Section
Repeated reflow soldering processes and soldering the module upside down are not recommended.
3.2.6
Wave soldering
Base boards with combined through-hole technology (THT) components and surface-mount technology (SMT)
devices require wave soldering to solder the THT components. Only a single wave soldering process is
encouraged for boards populated with u-blox 6 modules.
3.2.7
Hand soldering
Hand soldering is allowed. Use a soldering iron temperature setting equivalent to 350°C. Place the module
precisely on the pads. Start with a cross-diagonal fixture soldering (e.g. pins 1 and 15), and then continue from
left to right.
3.2.8
Rework
The u-blox 6 module can be unsoldered from the baseboard using a hot air gun. When using a hot air gun for
unsoldering the module, max 1 reflow cycle is allowed. In general we do not recommend using a hot air gun
because this is an uncontrolled process and might damage the module.
Attention: use of a hot air gun can lead to overheating and severely damage the module.
Always avoid overheating the module.
After the module is removed, clean the pads before placing and hand-soldering a new module.
Never attempt a rework on the module itself, e.g. replacing individual components. Such
actions immediately terminate the warranty.
In addition to the two reflow cycles manual rework on particular pins by using a soldering iron is allowed.
Manual rework steps on the module can be done several times.
