There is an article I produced for Global SMT magazine that lists many of
the potential issues to consider.

http://www.globalsmt.net/content/view/1791/68/ 

Many thanks


Bob Willis
2 Fourth Ave, Chelmsford, Essex, CM1 4HA England
Tel: (44) 1245 351502
Fax: (44) 1245 496123
Mobile: 07860 775858
 
www.ASKbobwillis.com
 
Book your place on Bob's "Step by Step Failure Analysis Workshop" 14th May
www.ASKbobwillis.com/faworkshops.pdf
 
 New "Printed Board Inspection & Quality Control" 3 July
www.ASKbobwillis.com/PCBworkshop.pdf 
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Richard Olsen
Sent: 05 May 2008 19:29
To: [log in to unmask]
Subject: [TN] BGAs on opposing sides

Hello,

I have a board before me with multiple BGA's on both sides. In some places
they oppose each other.
Does anyone have any manufacturing ideas for soldering the BGA's?
One I have heard is to mask the first side BGA's and heat through the mask,
BGA, board and finally the pads of the second BGA, finally removing the mask
when done. 

Thanks,
Rich


Richard Olsen
Quality Manager/ Sales & Customer Service
RNB Enterprises
17816 North 25th Avenue
Phoenix Arizona
85023-2108

Tel - 602-889-3463
Cel - 602-740-2244
Fax - 602-863-2274
Toll Free (800)-270-7585 
www.rnbent.com

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