--- Quote Start ---
Either if you have explicitely impedance-controlled boards or not, changing the I/O current strength effectively modifies the driver impedance.
--- Quote End ---
Exactly. Higher drive strength = lower driver impedance = less time required to charge the capacitance of the trace plus the load capacitance = faster rise/fall times = length of traces which must be considered as transmission lines is reduced.
I'm aware that the discussion was about single-ended I/O standards, thank you. Perhaps I should have been more clear: A source termination resistor "might" be required at the driver to fully match the driver impedance to the transmission line impedance.
Honored Contributor
