Mike,

If the pcb finish is not HASL, and there are no wave solder operations to
fill the via holes with solder, then it should not be necessary to use
thermal lands on ground planes. However, it does help us fabricators know
that there should be a hole connecting to the ground plane and it is not a
design error or oversight. We have to check for so many things these days
that it would inevitably be queried and therefore waste a lot of time.

If the finish is HASL then thermals are necessary.

Paul Gould
Teknacron Circuits Ltd
www.teknacron.com

-----Original Message-----
From: Mike Bailey +ADw-mbailey+AEA-MCCURDY.COM+AD4-
To: TechNet+AEA-IPC.ORG +ADw-TechNet+AEA-IPC.ORG+AD4-
Date: 21 December 1998 17:07
Subject: +AFs-TN+AF0- Via Configuration


We continue to see current designs incorporating via hole configurations
utilizing +ACI-wagon wheel+ACI- interconnects to plane layers.  Didn't the
purpose of this design become obsolete unless thru-hole leaded components
and wave soldering are necessary? Why not simply go with direct connects?
Can someone shed some light on this subject?

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