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| From [log in to unmask] Fri Dec 6 15: |
35:15 1996 |
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Fri, 6 Dec 1996 14:55:43 -0500 |
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I don't think anyone has provided the information that tenting vias is
required if you want to draw a vacuum for the tester. If there are a lot
of holes open and you do not use a rubber "blanket" to close the holes,
then you get "whisteling" and not a tight draw for pin contact.
The true way to tent is to use dry film. If this is not acceptable then
a dot pattern of UV cured ink on the bottom side is ok if there are no
test points that need to be open. Fab vendors have a lot of methods
with LPI.
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