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8/8/2019 Rework Procedure for Bga Modules
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Rework procedure for BGA modulesApplication Note80000NT10003a Rev. 0 - 29/09/06
8/8/2019 Rework Procedure for Bga Modules
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Rework procedure for BGA modules Application Note80000NT10003a Rev. 0 - 29/09/06
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Right reserved page 2 of 8
APPLICABILITY TABLE
PRODUCT PART NUMBER APPLICABILITY
EZ10-QUAD-PY 3990150467
GT863-PY 3990250466
GM862-GPRS 3990250631
GM862-QUAD 3990250655
GM862-QUAD-PY 3990250656
GM862-GPS 3990250657GM862-QUAD-PY 3990250658
GM862-QUAD 3990250659
GC864-QUAD 3990250675
GC864-PY 3990250676
GC864-QUAD-C2 3990250681
GE863-QUAD 3990250664
GE863-PY 3990250665
GE863-QUAD 3990250653
GE863-PY 3990250654
GE863-GPS 3990250660
GE863-PY 3990250661
GE863-QUAD 3990250662
GE864-PY 3990250650
GE864-QUAD 3990250648
8/8/2019 Rework Procedure for Bga Modules
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Rework procedure for BGA modules Application Note80000NT10003a Rev. 0 - 29/09/06
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Right reserved page 3 of 8
Contents
1 INTRODUCTION................................................................................................................42 PROCEDURE ....................................................................................................................5
2.1 Module preparation ................................................................................................................5 2.2 Prebaking ................................................................................................................................5 2.3 Part Removal...........................................................................................................................6 2.4 Site Preparation......................................................................................................................6 2.5 Solder Past Application .........................................................................................................6 2.6 BGA Placement and Reflow ..................................................................................................6 2.7 Cleaning ..................................................................................................................................7 2.8 Inspection................................................................................................................................7
3 Document Change Log....................................................................................................8
8/8/2019 Rework Procedure for Bga Modules
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Rework procedure for BGA modules Application Note80000NT10003a Rev. 0 - 29/09/06
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Right reserved page 4 of 8
1 INTRODUCTION
The rework concept of a Telit BGA GPRS module is basically the same of acommon plastic Ball Grid Array package component. To rework a BGA Telitmodule, a rework machine should be used. There are a lot of different kindsof machines in the market; Telit for example is using an APR series machineby Metcal. The principle consists in a metallic box (nozzle) to be used as anoven in which the BGA balls reflow, and a vacuum system lifts up thecomponent.Consider that after rework, the Telit module is no longer usable. Pleasefollow the below procedure in order to rework correctly the Telit modules.Precautions have to be taken in order to not damage the neighbourcomponents. Below the typical BGA rework process flow diagram:
Prebake
BGA Removal
Site Preparation
Solder PastApplication
BGA Placementand Reflow
Cleaning
Inspection
Prebake the entire board at 125 for at least 12 hours
Optimised reflow temperature/time profile
No overheating on neighbour components
Removal of high lead solder balls or any residue
Planarization
Cleaning
Solder past dispensing or flux only application
Optimised reflow temperature/time profile No overheating on neighbour components
No clean vs. clean Residue under BGA
Visual
Type of defects: opens, shorts, misorientation
8/8/2019 Rework Procedure for Bga Modules
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Rework procedure for BGA modules Application Note80000NT10003a Rev. 0 - 29/09/06
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Right reserved page 5 of 8
2 PROCEDURE
2.1 Module preparationSelect the correct size of nozzle referring to the dimensions of the module (could be that a standardtype is not suitable for the module, but in most cases the supplier of the rework machine is able tobuild custom size). Put some SMT glue points between the module PCB and the metallic frame of the
shield (see the rows in the picture below).Use a hot air solder to have a correct polymerisation of the glue. After the glue is hardened, unsolderthe module by using the rework machine (the glue should permit to raise the module without removethe metallic frame).
2.2 PrebakingSince the BGA packages are quite moisture sensitive, pre-rework precautions must be taken to avoidthe popcorning phenomenon. If the board has been exposed to out of dry-pack environment formore time than allowed, the entire board must be baked at 125C for at least 12 hours.
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8/8/2019 Rework Procedure for Bga Modules
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Rework procedure for BGA modules Application Note80000NT10003a Rev. 0 - 29/09/06
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Right reserved page 7 of 8
centre of the package, and the top surface side of the package. To achieve a minimal temperaturegradient, a slower ramp up rate (0.5C/s) and a lower peak reflow temperature is recommended.Additionally, the parts should be allowed to cool down by ambient air instead of blowing cool air on theparts with the nozzle. Blowing cool air on the component while it is still hot at the solder ball locationscreates an undesired temperature gradient which might brings to package warpage.
2.7 CleaningRemove all residues from the board. However, if no-clean solder paste/flux is used, cleaning is notrequired.
2.8 InspectionThis is the final step in the process. Visually inspect the outer rows of the solder joints to check forgross misalignment, joint quality, wrong orientation, board delamination, and damage of adjacentcomponents.
8/8/2019 Rework Procedure for Bga Modules
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Rework procedure for BGA modules Application Note80000NT10003a Rev. 0 - 29/09/06
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Right reserved page 8 of 8
3 Document Change Log
RReevviissiioonn DDaattee CChhaannggeessISSUE#0 29/09/06 Release First ISSUE# 0