I didn't see the original post, just the OMG reply.
Opened the link and thought Olympic Peninsula.
That is a big one!
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard D.
Sent: Monday, February 25, 2013 7:16 AM
To: [log in to unmask]
Subject: Re: [TN] 48-pin QFN via-in-pad solder slug problem.
OMG!
-----Original Message-----
From: Ed Popielarski [mailto:[log in to unmask]]
Sent: Friday, February 22, 2013 3:32 PM
To: [log in to unmask]; Stadem, Richard D.
Subject: RE: [TN] 48-pin QFN via-in-pad solder slug problem.
Production is a little sluggish today:
http://i97.photobucket.com/albums/l237/dawnsfall/6-10-05032bananaslug.jpg
Ed Popielarski
Engineering Manager
970 NE 21st Ct.
Oak Harbor, Wa. 98277
Ph: 360-675-1322
Fx: 206-624-0965
Cl: 949-581-6601
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard D.
Sent: Friday, February 22, 2013 10:29 AM
To: [log in to unmask]
Subject: Re: [TN] 48-pin QFN via-in-pad solder slug problem.
Most slugs I see have no problem with wetting. They leave a very telltale
streak on the sidewalk.
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Wayne Thayer
Sent: Friday, February 22, 2013 11:45 AM
To: [log in to unmask]
Subject: Re: [TN] 48-pin QFN via-in-pad solder slug problem.
Does the slug have a problem with wetting? (If you take a removed part and
put it on a hotplate, does solder readily wet it?)
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Alan Young
Sent: Friday, February 22, 2013 12:23 PM
To: [log in to unmask]
Subject: Re: [TN] 48-pin QFN via-in-pad solder slug problem.
Hi folks,
Please forgive me if this topic does not belong to this group.
Let me explain my predicament.
I'm a PCB layout guy who has been asked to look at a soldering issue we are
having with a 48-pin QFN 7mmx7mm [EMBER CORP - EM357-RTR], the solder slug
under the part is not soldering/bonding to the PCB. The pcb footprint is
made per the manufactures specification with a 5.3mm x 5.3mm solder slug pad
with 9 vias finished drill size of 0.254mm. There are no soldermask features
on the component or solder side over the vias.
When the board has been reflowed, all of the 48 pins solder well but the
slug has not bonded to the pcb. There are signs of solder in the slug vias
on the opposite side of the board. If the part is ripped off the board, the
slug is clean and solder free.
I do not have any information about the paste screen setup or the oven
profile.
The questions I have are;
1 - Any ideas on why this is happening?
2 - Are the vias in the slug causing this problem?
3 - Would soldermaks capping the vias on the component side help resolve
this?
4 - Would plugging (no capping) of the vias with epoxy help?
5 - Do north African sparrows fly faster then European sparrows (just seeing
if anybody is reading this :-)
I do have some photos and x-rays of the device if this will help.
Again any help or comments would be greatly appreciated.
Regards,
Alan Young.
This e-mail message and all attachments transmitted with it may contain
legally privileged and confidential information intended solely for the use
of the addressee. If you are not the intended recipient, you are hereby
notified that any reading, dissemination, distribution, copying, or other
use of this message or its attachments is strictly prohibited.
______________________________________________________________________
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]
______________________________________________________________________
______________________________________________________________________
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]
______________________________________________________________________
______________________________________________________________________
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]
______________________________________________________________________
______________________________________________________________________
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]
______________________________________________________________________
______________________________________________________________________
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]
______________________________________________________________________
|
