BGA chip re-balling / re-soldering service UK?

[mrclunk]

I'm repairing a Universal Audio interface that's not booting up and i think it needs a few BGA chips re-soldered.
If i put pressure on a chip during power up it will boot, no pressure no booty.
It's beyond my skill and kit to re-solder these sort of devices.

Anyone know a UK repair shop that does this sort of thing?
thanks.

 

[Khron]

Not 100000% certain reballing is necessary, i'd imagine "only" a reflow (with plenty of good flux), so the solder balls reconnect, should suffice. That's assuming there's no internal physical damage to that DSP chip in the first place.

Replacing it outright might as well make more sense (rather than taking care not to damage it during removal, then reballing, then resoldering).

Then again, one must wonder just how much back-and-forth goes on in the booting process, if one of the DSP chips can prevent the main processor from booting up all the way...

 

[gyraf]

..places that do cellphone repairs can most often be helpful with this sort of things also..

 

[mrclunk]

thanks, i'll have look at reflow. All the BGA re-ball shops i've emailed have not responded.

 

[JohnRoberts]

I have never attempted to DIY BGA packages but know people who have.

You could try your luck reflowing it using a hot air station.

JR

 

[RuudNL]

Some people use a paint stripper!...
(Although I don't think that is the best tool!)

 

[cyrano]

I even saw a YT vid where a alu foil basket on top of the chip was filled with some sort of fuel and set afire. Pretty sure that wouldn't work.

FWIW, most small reflow shops here are gone. Not exactly due to COVID, but due to the repair being unpredictable. Some last six months, others only a few days. These shops mainly did GPUs on Macbook Pro logic boards.

If there's no programming involved, I'd replace the chip if you can.

 

[Whoops]

Anyone know a UK repair shop that does this sort of thing?
thanks.

You should search for shops dedicated to computer logic board repairs.
In the US, Louis Rossmann is pretty well known for those kind of jobs, I guess you have to find the equivalent in the UK.

https://www.rossmanngroup.com/

 

[mrclunk]

I even saw a YT vid where a alu foil basket on top of the chip was filled with some sort of fuel and set afire.

Now that's my kind of repair!

I have a hot air station / gun but i'd rather pay a pro to do it properly.
I'll let you know if i have any joy.

 

[JohnRoberts]

If finger pressure helps it work, it may just be a marginal solder connection.

If you have a hot air station carefully heating it could reflow that solder connection...

JR

 

[radardoug]

Who came up with those dumb BGA's? Stupid!

 

[JohnRoberts]

Who came up with those dumb BGA's? Stupid!

packaging engineers trying to conserve PCB real estate, putting I/O on the bottom is actually pretty elegant for production, just a royal PIA for breadboarding and troubleshooting.

My first IC with pads on the bottom was a class D amplifier chip with heatsink on the bottom. It was all but impossible to breadboard. I had to layout a first cut PCB to even test it.

But I'm old, let the kids play with the modern tiny stuff.

JR

 

[Tubetec]

I did check with a Chinese computer/phone repair shop here before about BGA chip repair , they have all the gear and the expertise to do it , very competitive price too . There was one generation of xbox where the chips had a habit of melting off the board . Seeing as you have the issue narrowed down and the board taken out the time/charge should be minimal .

 

[Newmarket]

I did check with a Chinese computer/phone repair shop here before about BGA chip repair , they have all the gear and the expertise to do it , very competitive price too . There was one generation of xbox where the chips had a habit of melting off the board . Seeing as you have the issue narrowed down and the board taken out the time/charge should be minimal .

Did that include X-Ray inspection ?

 

[mrclunk]

If finger pressure helps it work, it may just be a marginal solder connection.

If you have a hot air station carefully heating it could reflow that solder connection...

JR

I do, just a bit scared of killing the chips.. How hot can i get them?

 

[Khron]

Lead-free solder melts at around 210C (which means the stuff around it ie. chip and pcb will need to be hotter than that). Ideally you'd want to closely and reliably measure the temperature of the pcb right next to the chip.

Datasheets often include reflow temperature vs time curves.

 

[JohnRoberts]

You can get the package hot enough to melt solder underneath it. Of course no reason to over heat it.

Try a little heat and if that doesn't work try again with a little more heat.

[edit- not easy but a little liquid flux around the edges might help /edit]

JR

 

[radardoug]

This is why these chips are so stupid. You have a bunch of solder connections to make which you cannot then check to see if they have made. There is the possibility of heatinng some parts enough, and other parts not enough. And all the possible contaminants etc which make the soldering process inexact.

 

[Tubetec]

in reply to Newmarkets question ,
Thats something I hadnt thought of Xray inspection ,
Use of xrays I would think to be covered under specific regulations here ,
Im happy to ask the Chinese guy at the shop next time I go into the city ,
his english isnt great ,so could be a bit of a challenge to explain ,ahahah .

In regards to using hot air on your board , a friend of mine who does a fair bit of surface mount work swears by the liquid flux , comes in a little syrynge, costly but good . The other thing he does is make a foil heatshield that goes around the edges of the chip being soldered so that other parts of the board arent heated needlessly .

 

[Newmarket]

in reply to Newmarkets question ,
Thats something I hadnt thought of Xray inspection ,
Use of xrays I would think to be covered under specific regulations here ,
Im happy to ask the Chinese guy at the shop next time I go into the city ,
his english isnt great ,so could be a bit of a challenge to explain ,ahahah .

In regards to using hot air on your board , a friend of mine who does a fair bit of surface mount work swears by the liquid flux , comes in a little syrynge, costly but good . The other thing he does is make a foil heatshield that goes around the edges of the chip being soldered so that other parts of the board arent heated needlessly .

Yes - I was thinking about the regulatory aspect too.
I'm not very familiar wrt X-Ray Safety Standards or what frequencies / hazards are involved in electronics inspection. But I get X-Rayed at my dentists and they get out of the room !
I'll hazard a guess that the typical mobile phone etc repair shop doesn't do X-ray inspection.
It's probably reasonable to just see if the device works after repair. If it doesn't or subsequently fails then I reckon the cost of rework or refund is much less than the investment in kit and associated training and certification would be. For manufacturers and CEMs etc obviously a different story.

By 'Liquid Flux' do you mean Solder Paste that comes in a syringe (or in a tub for larger quantities) ?
Yes - it is really good - BUT it doesn't have a great shelf life before it 'dries out'. Most stuff - pcbs / solder etc has almost indefinite shelf life regardless of any date on the product. But this stuff really does 'Go Off' - think of it as 'Electronic Cheese' (tm) and use it up quickly.

'Foil Heatshield' - yes - seen that a few times. I don't think it solves the 'BGA' problem though. (Or LGA for that matter).