Hummm, surprising.

DPAK are fairly light [~ 0.300 gm] and have a relatively huge solderable
surface [~ 47mm^2/0.07in^2].  This weight to solderable area 6.3mgm/mm^2
[4.1gm/in^2] is well within both
* "Zarro Limit" of 30 gm/in^2.
* "Willis Limit" of 44gm/in^2.

From this perspective, DPAK numbers are similar to a mini-MELF and to a
SOIC16.

Are you soldering the tab?  If so, how about:
* Loctite 3609 or equivalent
* Conveying the board differently
* Turning-down your bottom-side fans

Dave Fish


----- Original Message -----
From: "Kevin M. Bair" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, January 17, 2002 6:18 AM
Subject: [TN] D-Pak 2nd side reflow issues


> We are having problems with bottom side d-paks falling off when the top
> side of the board is being reflowed.  Has anyone had this problem, and if
> so, what have you done to correct it?
>
> Thanks for your help,
>
> Kevin Bair
> Assembly Engineer
> Teradyne, Inc.
>
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