Christy;

this is definitely a challenge;

One option is to "socket" one of the BGA's, but I've never come accross a good
"production" socket yet.

The other option is to use a solder "hierarchy", where one of the bga's is
applied with a lower melting point solder than the other.

A last option is to locally attach one of the bga's using a bga repair tool
which only locally heats the bga location.

hope this helps!

Jim Herard
KBL, Product Quality Engineering
IBM Microelectronics Endicott
t/l 857-7026

---------------------- Forwarded by Jim Herard/Endicott/IBM on 07-22-97 07:16 AM
 ---------------------------

        [log in to unmask]
        07-22-97 12:00 AM
Please respond to [log in to unmask] @ internet

To: [log in to unmask] @ internet
cc:
Subject: ASSY: BGA Mounting

Hello,

How does one mount two BGAs on a board, where one is on the
primary side and the other on the secondary side, directly beneath the
first?

Thanks in advance for your help.

Christy Graham
MICOM Communications Corp.
805-577-2210
[log in to unmask]

***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To subscribe/unsubscribe send a message <to: [log in to unmask]>   *
* with <subject: subscribe/unsubscribe> and no text in the body.          *
***************************************************************************
* If you are having a problem with the IPC TechNet forum please contact   *
* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask]      *
***************************************************************************



***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To subscribe/unsubscribe send a message <to: [log in to unmask]>   *
* with <subject: subscribe/unsubscribe> and no text in the body.          *
***************************************************************************
* If you are having a problem with the IPC TechNet forum please contact   *
* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask]      *
***************************************************************************