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View Full Version : Impedance matching in differential pairs


jatinp
06-26-2008, 02:54 AM
I am using Expedition PCB and CES to construct a PCB that uses several differential lines. I want the impedance to be matched to 100 ohm. I set the option in CES (Differential impedance Target) but the actual impedance turs out to be at least twice the targetted value each time.

Is there some other way to specify the impedance? Or is the auto-router not good enough to be able to satisfy the constraints?