Subject: | |
From: | |
Reply To: | |
Date: | Fri, 8 May 1998 13:30:19 -0700 |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
Vaughan, Ralph H wrote:
>
> Greeting,
>
> We are seeing a rash of glass surface mount diodes cracking somewhere
> during assembly. It isn't noticed until upper-level module assembly,
> but the #1 suspect is card assembly. All that have broken have been
> bonded to the board with an industry standard chipbonder, and some are
> mounted to the solder side of a wave-soldered polyimide board. The part
> size is .140w x .230L x .140h. We have run thermal cycles and wave and
> convection soldering on test samples, but can't reproduce the problem,
> so we suspect rough handling at the module levels.
> Anyone ever run into this?
>
> Ralph
>
> ################################################################
> 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 web site (http://jefry.ipc.org/forum.htm) for additional information.
> For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311
> ################################################################
Ralph -
Handling is a good assumption. Try especially where the board assembly
is flexed, like in a bed-of-nails tester. Ed Valentine
--
ProTronics, Inc.
861 Old Knight Road
Knightdale, NC 27545
Phone: (919) 217-0007, Fax: (919) 217-0050
http://www.protronics-inc.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 web site (http://jefry.ipc.org/forum.htm) for additional information.
For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311
################################################################
|
|
|