Lyon,

By 'pad drop' do you mean lifted pads? (Pads stayed with the BGA?)
Usually this means that there wasn't enough heat - that the solder was not melted in all locations.

Ben

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Lyon Yuan
Sent: Wednesday, September 04, 2013 6:40 AM
To: [log in to unmask]
Subject: EXTERNAL: [TN] BGA pad drop

guys,we found a few BGA pad drop after removed from pcba boards.what is reason to cause the issue

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