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Repair Tips
3. Lead-free product identificatio n
Youcan identify lead-free product by Philips-lead-free logo on PCB.
4. Lead-free product repair instruction
4.1 Use only lead-free Solder Alloy0622 14900106(1.2mm SAC305) or 0622 149
00108(1.0mm SAC305).
Remark: For leadfree soldering material, pl
ease visit www.alphametals.com website for
details. This is recommendedbyPhilips.
4.2 Use only adequatesolder toolsapplicable for lead-free soldering-tin. Thesolder toolmustbeable toreach atleast a
solder-temperature of 400 ,tostabilize theadjustedtemperature atthesolder-tip andtoexchange solder-tips for different
applications.
Small Passives/Actives to beremovedwith thermaltweezers
Automated systemfor ICandBGArepair (Microscope, Camera
,Beam split optics, Computer,Programmer,Heat
controllers, Vacuum system, Laser pointer)
Solder Hand-Tool(Adjustableintemperature height, Temperature shall be held constant,
Flexible tips)
4.3 Adjustyoursolder too
l so that a temperature around360 -380 is reached and stabilized atthesolder joint.
Heating-timeofthesolder-joint should not exceed~4sec. Avoidtemperatures above 400
otherwise wear-out oftips will
rise drastically andflux-fluidwill be destroyed.
Corrosion of Tool-Spikes can beavoidedwhen using SAC305 and a temperature ofless than 400
.
4.4Mixoflead-free solder-tin/parts with leaded soldering-tin/parts is possible but no t recommended. If nottoavoidclean
carefully thesolder-jointfrom old tin and re-solder with newtin.
4.5 Use only original spare-parts listed in the Service-
Manuals.Standard-material
(consumables)can also bepurchased at externalcompanies.
4.6 Special information for lead-free BGA-ICs:this ICs will be delivered in so-called
dry-packaging toprotect the IC againstmoisture an
dwith lead-free logo on it. This
packaging may only be opened shortly before it is used(soldered). Otherwise the
body ofthe ICgets wet insideandduring the heating time thestructure ofthe IC
will be destroyeddue to high(stea
m-)pressure.Ifthepackaging was openedbefore
usage the IC has to be heatedup for some hours (around90
)for drying (Take
attention for ESD-protection!)
5. Rework on BGA (Ball Gri dArray) ICs
General
Although(LF)BGA assembly yieldsareveryhigh, there may still bearequirementfor component rework. By rework, we
mean theprocess of removing the co
mponentfromthe PWB and replacing itwith anewcomponent. If an (LF)BGA is
removedfrom a PWB, thesolder ballsofthe component are deformeddrastically so theremoved(LF)BGA has to be
discarded.
DeviceRemoval
Asisthe case with anyc
omponentthat, it is essentialwhen removing an (LF)BGA, the board, tracks, solder lands, or
surrounding componentsarenotdamaged. To remove an (LF)BGA, the boardmustbe uniformly heatedtoatemperature
close to thereflow soldering temperature.Au
niformtemperature reduces the chanceofwarping the PWB.
To do this,werecommendthatthe board is heateduntil it is certain that all the jointsaremolten. Then carefully pull the
component off the boardwith avacuum nozzle.For
theappropriate temperature profiles, see the IC datasheet.
Area Preparation
When the componenthas been removed, thevacantICareamustbe cleanedbefore replacing the (LF)BGA.
Removing an ICoften leaves varying amountsof solder on the mounting
lands. This excessive solder can beremovedwith
either a solder sucker or solder wick. Theremaining flux can beremovedwith a brush andcleaning agent. After the board
is properly cleaned and inspected, apply fluxonthesolder landsand on the connection ballsofthe(
LF)BGA
Note: Do not apply solder paste, as this has shown toresult in problems during re-soldering.
DeviceReplacement
The last step in the repair process is tosolder thenewcomponent on the board. Ideally, the (LF)BGA should be
alignedunder a mi
croscope or magnifying glass.Ifthis is not possible,trytoalign the (LF)BGA with anyboardmarkers.
To reflowthesolder, apply a temperature profileaccording to the IC datasheet. Soasnotto damage neighbouring
components, itmaybenecessaryt
oreducesome temperatures andtimes.
More Informatio n
For more information on howto handle BGA devices, visitthis URL: http://www.atyourservice.ce.philips.com (needs
subscription). After login, select Magazine ,then go t
o Workshop Information .Here youwill findInformation on how
.to deal with BGA-ICs.
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