Subject: | |
From: | |
Reply To: | |
Date: | Fri, 12 Jan 2007 15:08:54 -0500 |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
Hi Bogert:
Is this an old board or is it a new design?. Was the
barrel deformed to the point that there were separation from the orifice
walls? Was it on only a board or was it many boards that had this
problem? If the barrel deformed and cracked, moisture could have
accumulated inside the pocket of separation. Once a pocket is created,
who know what can enter in and what problems going to create. Perhaps
the board was not properly supported when press fitting the studs, and
delamination occured. Only some thoughts.
Regards,
Ramon
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Jeffrey Bush
Sent: Friday, January 12, 2007 2:10 PM
To: [log in to unmask]
Subject: Re: [TN] Is this CAF?
Appears to be damage to package from - areas has excessive crazing and
meales.
Jeffrey Bush
Director, Quality Assurance and Technical Support
VERMONT CIRCUITS INCORPORATED
76 Technology Drive - POB 1890
Brattleboro, Vermont 05302
Voice - 802.257.4571 ext 37
Fax - 802.257.0011
<http://www.vtcircuits.com/> -----Original
Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of - Bogert
Sent: Thursday, January 11, 2007 6:26 PM
To: [log in to unmask]
Subject: [TN] Is this CAF?
January 11, 2007
This is an e-mail for all you CAF experts out there.
We have an OEM that manufactures a 10-layer VME backplane assembly that
has press-fit power studs installed in the backplane. The manufacturer
has experienced system level test failures. Some of these failures did
not occur during the initial testing but the assemblies failed at some
subsequent time during testing. The failure mode was shorting of the
+12V layer 1 to the +5V layer 3 via the pressed-in power studs. The OEM
had the backplane sent to an outside lab to determine the root cause of
the problem. After looking at the pictures taken from the evaluation,
it appears to me that the problem could be due to CAF because of the
damage done to the glass fibers in the FR4 board material. CAF is also
suspected since the test failures do not occur on initial testing of the
equipment. We verified that the PWB conductor spacing meets IPC-2221
requirements. Another factor is, we believe the OEM may have used some
Type H flux per J-STD-004. Not sure this is an issue unless some of the
flux residue entered the PWB internally via the press-fit power studs.
Steve Gregory was kind enough to post 13 pictures on his web site. They
are files GLB CAF # 1 through GLB CAF#13.
Can folks identify whether CAF could be the root cause of the problem?
Any help would be appreciated.
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing
per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to [log in to unmask]: SET
Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the
posts: send e-mail to [log in to unmask]: SET Technet Digest Search the
archives of previous posts at: http://listserv.ipc.org/archives Please
visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for
additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
|
|