Ian: 
            The short answer is do not do it. There are plenty of
responses on this matter in the archives. Specifically SAC BGA balls do
not solder reliably well using 63/37 SnPb solder, should reball. LF
terminations (Pure Sn) will solder fine except, must ensure whisker
mitigation methods are put in place.
        Regards,
        Ramon

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Braddock, Iain
Sent: Monday, November 20, 2006 6:48 AM
To: [log in to unmask]
Subject: Re: [TN] BGA anomaly


Not sure I worded this question so will ask again a slightly different
way as I didn't get any responses.

If one is reflow soldering ENIG boards with a mixture of SnPb & PbF part
(in particular PbF BGA's - SAC305) using a 63/37 SnPb solder what would
be the preferred peak temp / time above?

Regards,
        Iain.

-----Original Message-----
From: Braddock, Iain
Sent: 17 November 2006 08:35
To: [log in to unmask]
Subject: RE: [TN] BGA anomaly


Joyce,

I can't say it is preferable but how does one solder a board using SnPb
solder with the odd PbF part whilst trying to ensure the profile will
provide sufficient time above Solidus (Werner see I've learned!) to
enable a satisfactory soldered joint?

Regards,

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