[SI-LIST] Re: Chassis ground
- From: Larry Miller <ldmiller@xxxxxxxxxxxxxxxxxxxx>
- To: "'si-list@xxxxxxxxxxxxx'" <si-list@xxxxxxxxxxxxx>
- Date: Thu, 21 Jun 2001 17:24:17 -0700
Both schemes have been successfully used in networking boxes I have been
associated with.
The single-point "audio style" ground worked well in a "pizza box" chassis
that was fully sealed with screws, etc.
For chassis with plug-ins ("blades" in our terminology) we had much better
luck nailing everything down to the chassis, including digital ground. This
was especially true in gigabit systems. The plug-in PCBs were grounded to
the metal card carriers.
Larry Miller
-----Original Message-----
From: Alex Horvath [mailto:alexh@xxxxxxxxxxxxxxxx]
Sent: Thursday, June 21, 2001 9:29 AM
To: si-list@xxxxxxxxxxxxx
Subject: [SI-LIST] Chassis ground
I know most SI engineers work at the board level but I am often asked if
digital signal ground should be connected to the chassis ground at the board
(normally through standoffs). It seems to me that the chassis would be a
very high impedance signal path so in effect only DC currents would flow
thus becoming part of the power supply return. Is there any advantage to
keeping the chassis ground isolated from digital ground and connecting them
at a single point with the green AC wire? I'm asking from the point of view
of reducing EMI.
I'm talking about your typical high speed digital systems with multiple
boards in a large chassis. Also, assume no conductive connections to the
outside world (optical only, or unshielded Ethernet).
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List archives are viewable at: //www.freelists.org/archives/si-list
Old list archives are viewable at: http://www.qsl.net/wb6tpu
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List archives are viewable at: //www.freelists.org/archives/si-list
Old list archives are viewable at: http://www.qsl.net/wb6tpu
Other related posts:
