A good description of differential impedance can be found at
http://www.ansoft.com/~bracken/differential/differen.html
John Birkett TEL: (607)-563-5657
Amphenol Aerospace EMAIL: [email protected]
40-60 Delaware St. FAX: (607)-563-5714
Sidney, NY, 13838 URL: http://www.bcoenet.com
>----------
>From: Mark Nass[SMTP:[email protected]]
>Sent: Thursday, February 05, 1998 2:43 PM
>To: [email protected]
>
> We are laying out a board that has differential a SCSI bus on it.
>The specs say the that the differential impedance should be 110-135
>ohms.
> What is differential impedance? Is this the impedance between
>the 2 traces, or the impedance with respect to the plane?
>
>Thanks for your help,
>Mark Nass
>