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| From [log in to unmask] Fri Nov 15 17: |
56:33 1996 |
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Address,
We use .020 pitch devices extensively in our designs, 12mil lands with
8mil spacings. The conductors widths coming from these lands are
8mils (2.1 Cu thk; .0007 foil and .0014 plating). In addition to
other varibles, I believe the 8mil cond width is robbing much needed
heat for solderability. The 8mil cond width is out of context for
such lands and FPT devices.
Q: How much influence does the conductor really have on the wetting of
the land in reflow (No heavy copper planes in the 8 layer lay-up)?
Q: Is there a test that can be conducted to determine the amount heat
absorbed by the land.
I am in the process of convincing Hardware Design to reduce the
conductor width for the reason above, in addition to buying real
estate.
Please advise.
John Gulley
[log in to unmask]
972-578-3928
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