Subject: | |
From: | |
Reply To: | TechNet E-Mail Forum. |
Date: | Tue, 2 Mar 1999 19:34:20 EST |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
Hi Nancy -
Your question reminds me of a "concept" that was done - for a while - in the
early days of SMT. People would place a discreet component (usually a
decoupling capacitor) under a PLCC> There was no problem, per se, soldering
it, even the then common Convection/IR ovens (heat is conducted through the
substrate). A lot of folks were patting themselves on the back for this
wonderful PCB real estate saving set-up - particularly memory module
assemblers. What they soon found out was that, if there was a problem with
that inexpensive little discreet - component failure, bad joint, etc - they
had to remove an expensive PLCC to correct the problem. In light of the
exponential "fun" of removing and replacing a BGA to get at that 0402, my
recommendation is DON'T DO IT!
Phil Zarrow
SMT Process Consultant
ITM, Inc.
Durham, NH USA
www.ITM-SMT.com
################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe: SUBSCRIBE TechNet <your full name>
To unsubscribe: SIGNOFF TechNet
################################################################
Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312
################################################################
|
|
|