You are correct.  Please review technet archives. Basically, you need to
assure that the LF BGAs have plenty of Pb based solder on the pads, and
make sure the profile exceeds the PbFree melt point by at least 10C for
40 secs.  When you are done, the joints will look kind of crappy, but
have evenly distributed ugliness.

Wayne Thayer

>>> [log in to unmask] 6/15/2007 12:19 pm >>>
I am sure this has been beat to death.


If you have BGA's with lead free balls can you solder these
in a leaded process.

I have 7 different BGA's on this board

So if they are all leaded and I go with a leaded process life is good.
If they are all lead free and I go with a lead free process life is
good.

But what if I can't get them all in one flavor.

I know that one way is really bad. Isn't it soldering lead free parts
in
a leaded process? I could imagine that you won't get hot enough
to reflow the lead free balls. But what about using non lead free
BGA's in a lead free world.


Any input on this will really be appreciated.

Thank You
John Foster

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