Ken:

Teardropping is a procedure used to increase PWB manufacturability by creating extra pad material
to prevent drill breakout from the pad due to possible misregistration and layer thermal
stretching between any specific routing layer and the nc drill layer.

We don't include teardropping in part footprints, at least not yet.  As far as specifying
teardropping for BGA footprints IMHO I see no advantage as the size of the BGAs available today
don't cover a large enough area for misregistration and layer thermal stretching to be an issue.
Furthermore, teardropping is typically done as a post processing enhancement.  I believe adding
teardrops at the outset may limit routing resources to the point that a BGA may become unroutable
to some degree.  Do it at the end if at all.


Patel wrote:

> What is "Teardropping"? Please explain it with the pro's and con's.
>
> re,
> ken patel
>
> At 11:12 AM 6/26/98 -0400, Kuczynski Michael wrote:
> >Is anybody out there using "teardropping" on their BGA's footprints ?
> >
> >Any pro's/con's to doing this would be appreciated.
> >
> >Thanks In Advance,
> >
> >Michael Kuczynski       201-393-2122 (Phone)
> >Allied Signal           201-393-6688 (Fax)
> >688 Rt46E E/K4
> >Teterboro NJ 07608
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