*       Dave,
*
*       Joe Belmonte & Phil Zarrow, "Advanced Surface-Mount Manufacturing
Methods", Circuits Assembly, September 1996, page 36
*       Formula for secondary side mounting
*
Weight of components (g)                 <30
Total pad mating area (sq. inches)

Personally I find this too conservative.

Bev Christian
Nortel


> ----------
> From:         Dave Pick - process engineer[SMTP:[log in to unmask]]
> Sent:         Monday, March 23, 1998 10:38 AM
> To:   [log in to unmask]
> Subject:      [TN] Double Reflow: Component Weight vs. Pad Contact Area
> Ratio
>
> I have read somewhere of a component weight to SMT lead contact area ratio
> rule
> for double sided reflow. This ratio would be the maximum component weight
> to SMT
> pad contact area that would allow surface tension to overcome gravity. If
> the
> weight to surface area ratio is over this number, the part would fall off.
> Does
> anyone know what this ratio is?
>
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