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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

Using OCT-Rs with 50ohm impedance assumption makes a lot of designs "most likely to work", instead of "likely to work". It has a better chance than using min drive strength because min makes the transition time too slow for some cases. If the default is MIN, the system probably will not work. And not everyone can afford tools to simulate and analzye SI.