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Hello friends, in my process to learning and practice some works to repair electronic circuits, I want to reballing a OMAP, is Spain is possible buy a fx or nx deaded from 30€ to 50€ And this is a very good prices to work with the only risk of lose a 30/50€

Now the history of my new FX, I buy in a webpage of used articles from 30€ + shipment, this unit one day don’t turn on (I think a tipical ram problem) but the owner send to technical service, this service made a very bad work and don’t repair the unit but causes a serious damages , I found a big rocks of tin, the most curious is a some tin in the another side of OMAP, and I think this technical service practice a reballing in this unit.
If I put power, some components take a high temperature and I think the OMAP have some shorts to ground in the bad reballing.

I remove the OMAP and I see this:
I take a long time to clean tin to evaluate the damaged pads My next step is recover a damaged pads, and watch a lot of videos of the reballing process, and later try to solder my OMAP.

I see some videos where the user repair pads in the phones with a very very fine wire, any user know this wire to give me references? What tweezers need to work wit this wire?

This is a crazy job and need a lot of hours, but is only to learning, a fx in working order in Spain are around 100/150€ and is most cheaper buy another one!!

I think, if this operation have good results give me a big satisfaction.

Most of the ball pads look ok, I only done one reball on a power amp chip it did work for a few weeks then something else failed
I wish you well with you’re fever Oscar

Indeed a nice and interesting job.
For reballing you need some equipment. Tried to do it with an simple 64 ball BGA (the flash chip) but only with a hotair gun you have no chance. Needed pre-heater plate and apply correct temp-curve to above using IR.

With small BGA chips you can go with only hot air gun... for bigger ones you can use a preheater or electrical oven and a hot air gun with a lot of dexterity or an IR reballing station.

You put first the balls on the chip and heat it until they get fixed there, check that they all have the same size after this process, then put the chip on the board and find a way to fix it on the correct place then put it in the oven and start heating it up in small steps, but without going too hot - something up to 150gr C. Then you carefully take it out and apply heat over the chip with the hot air gun.

The most important thing here is using the correct balls .. and for a chip of this size you need the corresponding BGA stencil / template because you won't be able to arrange them by hand.

I found a jump wire of 0,02mm to recover pads, and a solder mask:
Now I need buy a good templete, I see some Kits but nothing specific to OMAP5948GXF, any user know socket name?

Next need buy a balls of tin, I look a lot of sizes, but I don’t know the correct size, I can buy all sizes but is very expensive to only use one time and one size, I want buy only a necessary materials and tools.

I have a heater with regulated degrees, I think I can made a good reballing process!!

I use Verowire for such repairs: https://www.verotl.com/verowire-wiring- ... er-79-1732

Go4IT wrote: ↑07 Feb 2020, 19:28 I use Verowire for such repairs: https://www.verotl.com/verowire-wiring- ... er-79-1732

wow been looking for this for ages i used to use all the time