Pete,
Do you know if the board supplier provides a certificate of compliance to the contract manufacturer on all orders shipped? You may be able to compare the most recent cert to previous ones and look for any changes or anomalies that may have occurred on this run.
Do you know if there was any rework that may have occurred by the contract manufacturer?
Is the CM using this board supplier for other assemblies, have they noticed any issues with other boards?
Someone's process is out of control. It just doesn’t happen on an entire lot, on a design that’s been in production with no previous issues, unless something has changed.
Ted
-----Original Message-----
From: DesignerCouncil [mailto:[log in to unmask]] On Behalf Of Pete
Sent: Tuesday, October 01, 2013 10:36 AM
To: [log in to unmask]
Subject: Re: [DC] Delamination - how often?
I'm reposting this from the "Program Management" thread just to get the topic back in one place.
RF = Radio Frequency.
This is the 4th rev of this board, using the same construction and basic design, same vendors. This is the first one that had any problems. Almost all of our boards have similar construction, we have had great success.
Failure was IPC-610 10.2.2, separation was between foil and laminate. One board was nearly 50% bubbles, evenly distributed on the bottom side. Only 2 actually failed (bottom side) per IPC-610, 3 others had delam that wasn't enough to reject, on both sides of the board. But we got strange performance (or no performance) from all the boards, so we assumed there was likely inner layer delam also. But a new development - we just found 2 resistors missing that pretty much hose the programming. Meaning we may actually only have 2 failures.
The fab shop reviewed all of their SPI data, everything seems to be OK. They had some overage from the run, so they ran thermal cycling (T260) 3x, no delam.
The circuit assembly house did pre-bake, ran solder samples twice, did everything right, with one exception. The boards are double side components, with BGAs, so they get 2 somewhat aggressive reflows. There are also PTH parts, these get hand soldered. I understand that they would run all 30 boards at the same time, but it would have been nice if the hand soldering operators had pointed out the delam prior to shipping. The hand soldering looks OK. He also should have noticed the missing resistors, they were on the placement file but not the BOM.
The assembly house is not blaming the fab house, he also offered the "it happens". He's also taking no responsibility. All three parties pretty much are in agreement that something happened at the fab house no a design that was somewhat difficult to build. But no one will assume liability for the time spent assembling the boards, that's what management wants to change in the future.
We fab boards on 2-3 day turns pretty often, going turnkey with the assembly vendor will slow that down. I have a very good working relationship with the fab house, makes things run smooth. They know our boards, don't require much documentation, will call me any time to keep jobs moving. Going turnkey will make that all third party communication. (Not to mention markup).
I wanted to post this on Technet, but some of the parties involved lurk there, I don't think it would be a good idea.
Pete
---------------------------------------------------------------------------------
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 16.0.
To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF DesignerCouncil.
To temporarily stop/(restart) delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL/(MAIL) For additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
---------------------------------------------------------------------------------
______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
For more information please contact helpdesk at x2960 or [log in to unmask]
______________________________________________________________________
---------------------------------------------------------------------------------
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 16.0.
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF DesignerCouncil.
To temporarily stop/(restart) delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL/(MAIL)
For additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
---------------------------------------------------------------------------------
|
