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Reply To: | TechNet E-Mail Forum. |
Date: | Tue, 19 Oct 1999 11:24:50 -0400 |
Content-Type: | text/plain |
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I'm don't think it makes sense to specify a class 3 annular ring requirement (1
mil annular ring) just because you have a high reliability application. My
feeling is class 2 with some breakout allowed (provided minimum spacing to
adjacent line is OK and line entry to land is adequately flared) will last
forever for 99% of applications. A class 3 annular ring only makes sense for
some kind of application (military?) which sees huge temperature swings. By
blanket specifying class 3 for a commercial/ordinary application because you
want high reliability, you are getting overkill on the annular ring requirement
and unnecessarily impacting manufacturability.
Jonathan Whitcomb IBM Endicott 607-757-1326 [log in to unmask]
Dept T49G bldg 257-2 1701 North St. Endicott NY 13760 aisle H office X013
pager 2930 fax 607-757-1156
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