And help yourself by reducing the via size if you can.
Dave C
CSI

-----Original Message-----
From: Franklin D Asbell [mailto:[log in to unmask]]
Sent: Monday, August 30, 2004 12:05 PM
To: [log in to unmask]
Subject: Re: [TN] tented Via


If there is nothing for the solder to wet to (absence of metal???) in the
via how will current flow through the via???

I would say plug the vias instead of tenting them. With tenting you are
applying solder mask solely to the pad surface, not the via hole wall, this
allows for an opening from the top of the board into the via hole that is
easily filled with solder, solder that can rob needed solder from the leads,
or worse, ball up and redeposit itself in unwanted places such as between
non-common leads...a short.

Plug the vias from the top side, provide the fabricator with a plugged via
gerber file detailing those vias to be plugged, specify this is a separate
process from solder mask coating. The process is pretty simple, using the
plug artwork the vias are filled with solder and cured, then the regular
artwork is used with vias tented.

This will ensure solder will not enter the vias thus robbing the leads and
will also prevent solder shorted leads...

Franklin

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