Issues concerned with re-balling FPGAs

[yonfan]

I currently have an issue on some of my board designs due to leaded BGA devices becoming obsolete and only the lead-free variants being available.

The solution I have requires me to get the devices re-balled.

Does anybody have any experience of re-balling devices? are there any quality/relaibility issues concerned with this? Are there any web resoources on this issue ?

Many thanks

Jon

 

[Johnson]

Re: Re-Balling FPGAs

Take a look at SMT magezine, I have seen a ad. related to repaire but still useable to this issue!

 

[banjo]

Re: Re-Balling FPGAs

We have had FPGAs and other parts reballed with pretty good success. The yield is not 100%, but is at least above 90% with a good rework shop. The limiting factor seems to be the PCB you are mounting to. PCB can only take so many heat cycles before the pads start to pull off and the board delaminates. In most of our cases, the FPGAs were pulled due to bridges or opens under the parts. The FPGAs were removed, reballed, and reapplied to the same PCB. Therefore, the minimum complete thermo cycles were three. If the reballed FPGA did not work, we had a lower yield attempting to remove and resolder for yet again.

The trick is finding a shop that really knows BGAs. Having the reballing station is only part of the equation. They have to be skilled at using it. Ask your local distributor about who they would recommend. You may also be able to remove the FPGAs and have them factory reballed, depending on your volume.

---- Steve