I would weight the cost of placement, saved real estate (if it allows
decreasing board size) and layout/routing time to the fabrication costs.
Plane Capacitors can be an expensive approach but may save money depending
on the design criteria.

-----Original Message-----
From: Kuczynski Michael [mailto:[log in to unmask]]
Sent: Thursday, July 13, 2000 11:32 AM
To: [log in to unmask]
Subject: Re: [DC] Plane Capacitors


A couple of years ago (@ a previous company), we did 2 boards w/ HADCO as an
experiment. (Voice and data cards which went in card cage, 12" x 16")
They were existing designs and only left the larger caps on the board
(.33uF)
The boards we just as quiet with the plane and no anomilies. (about 2 weeks
of
constant test)

Being it was just a test and I left shortly after, I don't know if they went
foward w/ the idea.

I know it saves time in placement and routing.
Frees up routing room.
I would still make provision for added caps @ critical components.


Michael Kuczynski       Librarian/Sr. Designer
L3 Communications       201-393-2122 (Phone)
Space & Navigation      201-393-6681 (Fax)
699 Rt46E PL1/H13       Mail Stop PL1/J8
Teterboro NJ 07608
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