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Altera_Forum's avatar
Altera_Forum
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18 years ago

Default drive strengths for Stratix III and Cyclone III

Note that Stratix III and Cyclone III default drive strengths on most I/O standards are set to OCT Rs for better signal integrity. On previous families they were set to max drive strength for best pe...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
18 years ago

I'm not convinced this is the best idea, I agree that this solution is better than the previous setting of MAX drive strength but:

1) We are assuming a 50ohm scheme.

2) I believe that a default setting of MIN drive strength would be better as:

A) No matter how badly anyone lays out their PCB, this will result in the least overshoot / ringing etc and hence will cause the least electrical stress on the other devices on the board.

B) Min drive strength would probably result in most designs NOT just working like magic, and hence would result in engineers actually thinking about the optimum drive strength setting for their system.