=3DI believe you are correct, it is still a transmission line. The =
comments in
=3Dthe EETimes article sound like they're coming from a marketing type.
=3DBut that said, I do believe that the settling times on this new VME
=3Dbackplane could be improved, and the loads could be more consistent. =
Every
=3Dboard would now see the same load. Currently, the board in slot 1 =
really
=3Dsees a different load than the board in the middle of the backplane. =
Also,
=3Dif the board in slot 1 was the driver, the board in slot 2 sees a very =
ugly
=3Dsignal compared to the board in slot 21....
=3DA major drawback on this approach is the huge routing resources needed =
to do
=3Da star topology, instead of a daisy-chain, on a 21 slot VME BUS!
Do you think the trace lengths are balanced? i.e., Is the length from
slot 9 tromboned to the same length as the trace from slot 1 to the
star? That would truly make every board see the same load and the
same transmission line. That would eliminate the large slot-to-slot
difference that exists now.
--
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D
Mike Mayer Artesyn Communication Products, =
Inc
Madison, WI
http://www.artesyn.com/cp
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D
**** To unsubscribe from si-list: send e-mail to =
[email protected]. In the BODY of message put: UNSUBSCRIBE =
si-list, for more help, put HELP. si-list archives are accessible at =
http://www.qsl.net/wb6tpu/si-list ****
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Date: Wed, 16 Sep 1998 10:46:18 -0500 (CDT)
Message-Id: <[email protected]>
From: Mike Mayer <[email protected]>
To: [email protected]
Cc: [email protected]
In-Reply-To:
<F40D462D6FF2D11182E800805F95330DFA0E71@fl51m01.space.honeywell.com>
([email protected])
Subject: Re: [SI-LIST] : New VME Backplane -- Star Layout
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