Motorola MTM800 FuG ET, Basic Service Manual

Page: 61 / 120

Maintenance 6 - 5
For soldering components with Hot-Air or infra red solder systems, please check your user guide
of the solder system to get information on solder temperature and time for the different housings
of the integrated circuits and other components.
Pre-baking of Integrated Circuits
Electronic components are generally coated with plastic material which has the nature of not being
waterproof. If kept unsealed the components can absorb humidity. When soldered to the board
(especially with reflow techniques) the sudden change in temperature can cause fissure or crack
which can result in malfunction or damage.
To avoid this problem these moisture sensitive components (MS) should be stored and shipped in a
sealed wrapping (dry pack). Processing must take place only with “dry components” when an
uninterrupted dry storage can be guaranteed, otherwise the components have to be pre-baked.
If a reflow procedure takes place close to MS components the whole board must be pre-baked.
* Out of dry package Moisture Sensitivity Level (MSL) 2 : 1 year
2A : 1 month
3 : 168 hrs
** Applicable for newer board revisions (PCB: 8471860Y12 onwards)
Table 6-3 List of moisture sensitive components
Part. No. MSL* Description
5186988J77 3 Tx Power Control IC
51014650001/
51012325001**
3 Power Management IC
5164015H28 3 RF IC
51012156001/
51012239002**
3 NAND
51012058002 3 Mobile DDR
51012110004/
51012295005**
3 Dual Core Processor
5115443H02 3 LNA
5187512V01 3 DCR Base-band Mixer
51012152001 3 Ethernet Transceiver