Are there any of the following on the PWB near this exothermic event site? - Ground holes with retaining screws - Narrowing of voltage planes - Internal planes too close to keep out zone - Please review PWB drawing. Victor, -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Paul Reid Sent: Wednesday, September 05, 2007 6:33 AM To: [log in to unmask] Subject: Re: [TN] Help needed on motherboard failure analysis Hi Gil, I have seen this sort of failure a few time, although not that dramatic, and they were attributed to CAF. The product passed burn-in and testing after assembly, then failed months later in the field. A cross section from a similar hole, near the failure site, one that is not damaged, may demonstrate a laminate crack, delamination or crazing. If there is a pathway (crazing, dielectric cracks), a CAF type failure mode may develop in humid, thermal cycling environment. Sincerely, Paul Reid Program Coordinator PWB Interconnect Solutions Inc. 235 Stafford Rd., West, Unit 103 Nepean, Ontario Canada, K2H 9C1 613 596 4244 ext. 229 [log in to unmask] <mailto:[log in to unmask]> -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Zilber Gil Sent: Tuesday, September 04, 2007 1:26 PM To: [log in to unmask] Subject: [TN] Help needed on motherboard failure analysis Hi, Recently one of our motherboard failed. It reaches very high temperature that melts the copper and explodes shooting (from the side of the board) the melt copper to over 20 cm. the shooting hole cause delamination of the board in the area. A lot of black smoke and was also seen. The max voltage of the board is about 50V. The board worked fine for more then a year. What could be the failure mechanism? Could it be due to conductive filament formation (although the PCB should be free of that)? Thanks Gil Zilber Elta Systems The information contained in this communication is proprietary to Israel Aerospace Industries Ltd. and/or third parties, may contain classified or privileged information, and is intended only for the use of the intended addressee thereof. If you are not the intended addressee, please be aware that any use, disclosure, distribution and/or copying of this communication is strictly prohibited. If you receive this communication in error, please notify the sender immediately and delete it from your computer. Thank you. This message is processed by the PrivaWall Email Security Server. --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 15.0 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 15.0 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 -----------------------------------------------------