Electronics Forum | Thu May 01 13:58:31 EDT 2008 | mmjm_1099
In our house we have had some of our BGA's reballed because it was a lead-free part and wanted to place on a leaded assembly. Hope this helps.
Electronics Forum | Thu Nov 03 10:49:11 EST 2005 | russ
This is what I would propose, Place and reflow the board without the BGA with your lead process, remove the solder from the BGA pads if you cannot mask off the apertures in your stencil. Then place the BGA and reflow to SAC requirements with a rewo
Electronics Forum | Thu May 01 12:46:19 EDT 2008 | dphilbrick
Thanks for the link Samir. Although this thread does have some good info in it I don't think it is hitting the exact point I am trying to resolve. This seems to talk to a one profile fits all for running lead and lead free paste. I want to know about
Electronics Forum | Mon Jul 06 16:54:51 EDT 2020 | emeto
For repair - passive components you can solder with corresponding chemistry. You remove the old part, clean the pad surface. Now you can match component and solder as needed. BGA is more difficult as they already balled the part with certain chemistr
Electronics Forum | Thu Mar 01 11:47:20 EST 2007 | Wagoner
Run the lead free BGA side first. Then run the tin lead side second. We do this on some boards so that we don't overheat the components on the second side. There is no reason that the lead free solder needs to reflow on the second pass.
Electronics Forum | Wed Oct 06 12:45:01 EDT 2010 | blnorman
I've seen studies were Pb-free BGAs in a leaded process have no reliability issues when a lead free profile is used. Pb-free profile ensure proper ball collapse and solder joint formation.
Electronics Forum | Thu Nov 03 12:52:23 EST 2005 | Amol
the only problem i see here is the neighboring components (depending upon the component density) will surely undergo a second reflow during the rework stage for the BGA. this way the only lead you will have in the BGA assembly is if you are using HA
Electronics Forum | Tue Dec 14 16:43:53 EST 2004 | Guest
Yes, the (large) company where I work has the policy not to use leadfree BGA's in the "old" process, so it's not unusual. Be prepared to have more customers having this opinion.
Electronics Forum | Thu Jan 05 15:09:37 EST 2006 | grantp
Hi, What studies? Can you post a link? I am not sure what the difference is between a ceramic BGA that the high temp solder ball is not expected to collapse, and a lead free solder ball that's run through a lead process and also does not collapse b
Electronics Forum | Tue Mar 07 12:06:56 EST 2006 | billyd
muse- I agree with you. You should never mix chemistries if you don't absolutely have to. If you HAVE to, you can go with a lead free BGA with leaded paste with much fewer defects than the other way around.
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