User's Manual

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LAN/BT System Integration Manual
4.HandlingandSoldering
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4.1Packaging,shipping,storageandmoisturepreconditioning
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HandlingRequirements
DONOTTOUCHANYPINOFWIFIMODULEWHILEASSEMBLYING.
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Moisturepreconditioning
ThisWLAN/BTmodulemeetsMSL3.PleasefollowJ‐STD‐033Btohandlethismodule.
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4.2SolderingRequirements
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4.2.1SolderingIronSoldering
SolderTemperature:350
o
C
ImmersionDuration:2~3seconds
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4.2.2ReflowProfile
 Aconvectiontype ‐solderingovenisstronglyrecommendedovertheinfraredtyperadiationoven.
Convectionheatedovensallowprecisecontrolofthetemperatureandallpartswillbeheatedupevenly,
regardlessofmaterialproperties,thicknessofcomponentsandsurfacecolor. 
Considerthe"IPC‐7530Guidelinesfortemperatureprofilingformasssoldering(reflowandwave)
processes.”
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PreheatPhase 
Initialheatingofcomponentleadsandballs.Residualhumiditywillbedriedout.Pleasenotethatthis
preheatphasewillnotreplacepriorbakingprocedures.
Tem pe ratureriserate:max3°C/sIfthetemperatureriseistoorapidinthepreheatphaseitmaycause
excessiveslumping.
PreheatTime:60~120secIfthepreheatisinsufficient,ratherlargesolderballstendtobegenerated.
Conversely,ifperformedexcessively,fineballsandlargeballswillbegeneratedinclusters.
EndTemperature:140~190°CIfthetemperatureistoolow,non‐meltingtendstobecausedinareas
containinglargeheatcapacity.
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Heating/ReflowPhase 
Thetemperaturerisesabovetheliquidstemperatureof227°C.Avoidasuddenriseintemperatureasthe
slumpofthepastecouldbecomeworse.
Limittimeabove227°Cliquidstemperature:30~70sec
Peakreflowtemperature:235~250°C
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CoolingPhase 
Acontrolledcoolingavoidsnegativemetallurgicaleff ects(solderbecomesmorebrittle)ofthesolderand
possiblemechanicaltensionsintheproducts.Controlledcoolinghelpstoachievebrightsolderfillets
withagoodshapeandlowcontactangle.
Tem pe raturefallrate:max4°C/s
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