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Altera_Forum
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13 years ago

Driving terminated controlled impedance trace single ended

Hi, I'm sure this comes up a lot but I couldn't find an exact match to my query. Consider a single ended 3.3V LVTTL Cyclone IV output, driving into a 50 ohm trace with far end parallel termin...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

Yes, this is a problem. You can't drive a 50 ohm doubly terminated trace with an LVTTL output. You need 3.3V/100 = 33mA and you only have 4mA.