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Repair Tips
3. Lead-free product identification
You can identify lead-free product by Philips-lead-free logo on PCB.
4. Lead-free product repair instruction
4.1 Use only lead-free Solder Alloy 0622 149 00106(1.2mm SAC305) or 0622 149
00108(1.0mm SAC305).
Remark: For leadfree soldering material, please visit www.alphametals.com web
site for
details. This is recommendedbyPhilips.
4.2 Use only adequatesolder toolsapplicable for lead-free soldering-tin. Thesolder tool mustbeable to reach atleast a
solder-temperature of 400 ,tostabilize theadjustedtemperature atthesolder-tip and to exchangesolder-tips for different
applications.
Small Passives/Actives to beremovedwith thermaltweezers
Automated systemfor IC and BGA repair (Micros
cope,Camera,Beam splitoptics,Computer,Programmer,Heat
controllers,Vacuum system, Laser pointer)
Solder Hand-Tool (Adjustableintemperature height, Temperature shall be held constant,
Flexible tips)
4.3 Adjustyoursold
er tool sothat a temperature around 360 -380 is reached and stabilized atthesolder joint.
Heating-time of thesolder-joint should not exceed~4sec. Avoidtemperatures above 400
otherwise wear-out of tips will
rise drastically and flux-fluidwill be destroyed.
Corrosion of Tool-Spikes canbeavoidedwhenusing SAC305 and a temperature of less than400
.
4.4 Mixoflead-free solder-tin/parts with leaded soldering-tin/partsispossible but not recommended. If not to avoidclean
carefully thesolder-joint from old tin and re-solder with newtin.
4.5 Use only original spare-parts listed inthe Servi
ce-Manuals.Standard-material
(consumables)can alsobepurchased at externalcompanies.
4.6 Special information for lead-free BGA-ICs:this ICs will be delivered in so-called
dry-packaging to pr
otect the IC againstmoisture and with lead-free logo on it. T his
packaging mayonlybe opened shortly before it is used(soldered). Otherwise the
body of the IC gets wet insideand during the heating time thestructure of the IC
will be d
estroyeddue to high (steam-)pressure.Ifthepackaging was openedbefore
usage the IC has to be heatedup forsome hours (around 90
)for drying (Take
attention for ESD-protection!)
5. ReworkonBGA(Ball GridArray) ICs
General
Although (LF)BGA assembly yieldsareveryhigh, there may still bearequirement for component rework. By rework, we
meantheprocess of removing the component from the
PWB and replacing itwith a newcomponent. If an(LF)BGAis
removedfrom a PWB, thesolder balls of the component are deformeddrastically sotheremoved(LF)BGAhas to be
discarded.
DeviceRemoval
Asisthe case with any component tha
t, it is essentialwhen removing an(LF)BGA,the board, tracks, solder lands,or
surrounding componentsarenot damaged. To removean(LF)BGA,the boardmustbe uniformly heatedtoa temperature
close to thereflow soldering temperature.Auniformtempera
ture reduces the chance of warping the PWB.
Todothis,werecommend thatthe board is heateduntil it is certainthat all the jointsaremolten. Thencarefully pull the
component off the boardwith a vacuum nozzle.For theappropriate temperature profiles,
see the IC datasheet.
Area Preparation
Whenthe component has been removed, the vacant IC area mustbe cleanedbefore replacing the (LF)BGA.
Removing anICoftenleaves varying amounts of solder on the mounting lands. This excessivesolder
canberemovedwith
either a solder sucker orsolder wick. Theremaining flux canberemovedwith a brush and cleaning agent. After the board
is properly cleaned and inspected, apply flux on thesolder landsand on the connection balls of the(LF)BGA
Note
: Do not apply solder paste, as this has shown to result in problems during re-soldering.
DeviceReplacement
The last step inthe repair process is to solder the newcomponent on the board. Ideally, the (LF)BGA should be
alignedunder a microscope or m
agnifying glass.Ifthis is not possible,trytoalign the (LF)BGA with any boardmarkers.
To reflow thesolder, apply a temperature profileaccording to the IC datasheet. So as not to damage neighbouring
components, itmaybe necessarytoreducesom
e temperatures and times.
More Information
For more information on how to handle BGA devices,visitthis URL: http://www.atyourservice.ce.philips.com (needs
subscription). After login, select Magazine ,thengoto Worksho
p Information . Here you will find Information on how
.to deal with BGA-ICs.
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