Hi BLM,

you do not mention if the bridges you see are following reflow, or, most
likely wave soldering.

For wave, we found 10 mils to be a good distance to avoid shorts, so maybe
you should play a little with the soldering parameters.
Another solution, better, is to plug the vias from the side giving the
trouble.

I know this is not the answer you wanted, but I know nothing of specs on
this matter and I felt the need to comment, since the ol' boys are very
quiet lately.

Ioan

> -----Original Message-----
> From: Brad L. Matthies [SMTP:[log in to unmask]]
> Sent: Friday, March 31, 2000 1:27 PM
> To:   [log in to unmask]
> Subject:      [TN] Via Hole Placement.
>
> TN,
>
> We are experiencing some manufacturing problems (solder bridging) and
> have linked them to via hole placement.  The particular assembly we are
> manufacturing has multiple via holes that are within approximately 15
> Mils of SMT lands.  Does anyone have a resource that spells out safe
> distances of via holes to SMT lands that they can pass along?  We are
> getting ready to approach the design group for this product and are
> looking for a qualified resource of information that we can use as well
> as the design group.
>
> Thanks,
> BLM
>
> ##############################################################
> TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
> ##############################################################
> To subscribe/unsubscribe, send a message to [log in to unmask] with
> following text in
> the body:
> To subscribe:   SUBSCRIBE TECHNET <your full name>
> To unsubscribe:   SIGNOFF TECHNET
> ##############################################################
> Please visit IPC web site (http://www.ipc.org/html/forum.htm) for
> additional
> information.
> If you need assistance - contact Keach Sasamori at [log in to unmask] or
> 847-509-9700 ext.5315
> ##############################################################

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
##############################################################