Philips BDL4785SL/00, Service Manual

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3. Le a d- f ree product identi f ic a tion
You c a n identi f y le a d- f ree product by Philips-le a d- f ree lo g o on PCB.
4. Le a d- f ree product rep a ir instruction
4.1 Use only le a d- f ree S older Alloy 06 22 149 00106(1. 2mm S AC305) or 06 22 14900108(1.0 mm S AC305).
Re ma rk: For le a d f ree solderin g ma teri a l, ple a se visit www. a lph am et a ls.co m website f or det a ils. This is reco mm ended by Philips.
4. 2 Use only a dequ a te solder tools a pplic a ble f or le a d- f ree solderin g -tin. The solder tool m ust be a ble to re a ch a t le a st a solder-te m per a ture o f 400, to
st a bilize the a d j usted te m per a ture a t the solder-tip a nd to exch a n g e solder-tips f or di ff erent a pplic a tions.
Sma ll P a ssives/Actives to be re m oved with ther ma l tweezers
Auto ma ted syste m f or IC a nd BGA rep a ir (Microscope, C am er a , Be am split optics, Co m puter, Pro g r amm er, He a t controllers, V a cuu m syste m , L a ser
pointer) S older H a nd-Tool (Ad j ust a ble in te m per a ture hei g ht, Te m per a ture sh a ll be held const a nt, Flexible tips)
4.3 Ad j ust your solder tool so th a t a te m per a ture a round 360 -380 is re a ched a nd st a bilized a t the solder j oint.
He a tin g -ti m e o f the solder- j oint should not exceed ~ 4 sec. Avoid te m per a tures a bove 400 otherwise we a r-out o f tips will rise dr a stic a lly a nd f lux- f luid will
be destroyed. Corrosion o f Tool- S pikes c a n be a voided when usin g S AC305 a nd a te m per a ture o f less th a n 400.
4.4 Mix o f le a d- f ree solder-tin/p a rts with le a ded solderin g -tin/p a rts is possible but not reco mm ended. I f not to a void cle a n c a re f ully the solder- j oint f ro m old
tin a nd re-solder with new tin.
4.5 Use only ori g in a l sp a re-p a rts listed in the S ervice-M a nu a ls. S t a nd a rd- ma teri a l (consu ma bles) c a n a lso be purch a sed a t extern a l co m p a nies.
4.6 S peci a l in f or ma tion f or le a d- f ree BGA-ICs: this ICs will be delivered in so-c a lled dry-p a ck ag in g to protect the IC aga inst m oisture a nd with le a d- f ree
lo g o on it. This p a ck ag in g ma y only be opened shortly be f ore it is used (soldered). Otherwise the body o f the IC g ets wet inside a nd durin g the he a tin g
ti m e the structure o f the IC will be destroyed due to hi g h (ste am -) pressure. I f the p a ck ag in g w a s opened be f ore us ag e the IC h a s to be he a ted up f or
so m e hours ( a round 90 ) f or dryin g (T a ke a ttention f or E S D-protection!)
5. Rework on BGA (B a ll Grid Arr a y) ICs
Gener a l
Althou g h (LF)BGA a sse m bly yields a re very hi g h, there ma y still be a require m ent f or co m ponent rework. By rework, we m e a n the process o f re m ovin g
the co m ponent f ro m the PWB a nd repl a cin g it with a new co m ponent. I f a n (LF) BGA is re m oved f ro m a P WB, the solder b a lls o f the co m ponent a re
de f or m ed dr a stic a lly so the re m oved (LF)BGA h a s to be disc a rded.
Device Re m ov a l
As is the c a se with a ny co m ponent th a t, it is essenti a l when re m ovin g a n (LF) BGA, the bo a rd, tr a cks, solder l a nds, or surroundin g co m ponents a re not
d amag ed. To re m ove a n (LF)BGA, the bo a rd m ust be uni f or m ly he a ted to a te m per a ture close to the re f low solderin g te m per a ture. A uni f or m te m per a ture
reduces the ch a nce o f w a rpin g the PWB.
To do this, we reco mm end th a t the bo a rd is he a ted until it is cert a in th a t a ll the j oints a re m olten. Then c a re f ully pull the co m ponent o ff the bo a rd with a
v a cuu m nozzle. For the a ppropri a te te m per a ture pro f iles, see the IC d a t a sheet.
Are a Prep a r a tion
When the co m ponent h a s been re m oved, the v a c a nt IC a re a m ust be cle a ned be f ore repl a cin g the (LF) BGA. Re m ovin g a n IC o f ten le a ves v a ryin g
am ounts o f solder on the m ountin g l a nds. This excessive solder c a n be re m oved with either a solder sucker or solder wick. The re ma inin g f lux c a n be
re m oved with a brush a nd cle a nin g ag ent. A f ter the bo a rd is properly cle a ned a nd inspected, a pply f lux on the solder l a nds a nd on the connection b a lls o f
the (LF)BGA
Note: Do not
a pply solder p a ste, a s this h a s shown to result in proble m s durin g re-solderin g .
Device Repl a ce m ent
The l a st step in the rep a ir process is to solder the new co m ponent on the bo a rd. Ide a lly, the (LF) BGA should be a li g ned under a m icroscope or
mag ni f yin g g l a ss. I f this is not possible, try to a li g n the (LF)BGA with a ny bo a rd ma rkers. To re f low the solder , a pply a te m per a ture pro f ile a ccordin g to
the IC d a t a sheet. S o a s not to d amag e nei g hbourin g co m ponents, it ma y be necess a ry to reduce so m e te m per a tures a nd ti m es.
More In f or ma tion
For m ore in f or ma tion on how to h a ndle BGA devices, visit this URL: http://www. a tyourservice.ce.philips.co m (needs subscription). A f ter lo g in, select
M aga zine, then g o to Workshop In f or ma tion. Here you will f ind In f or ma tion on how to de a l with BGA-ICs.