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Honored Contributor
Honored ContributorCyclone EP1C20 slew rate
Where can I find the slew rate(rise time/fall time) of EP1C20F400c8 Looked in the cyclone family data sheet. could not find it. I want to reduce the slew rate from default to something slower.
Altera_ForumHonored Contributor
Honored Contributor --- Quote Start --- Are rise/fall time that difficult to put in a data sheet. --- Quote End --- Most likely it isn't. Put it in as a specification means it has to be tested. Apparently Altera ried to avoid this. Actual rise- and fall times depend a lot on load capacitances. Newer chips, e.g. Cyclone III have a big list of specifications, that allow to estimate the IO speed depending on current strength and load capacitances. Similar data aren't given for Cyclone. But detailed empirical rise- and fall times for most devices, also Cyclone, are given in the ibis files available at Altera.com. Nevertheless, most designers prefer to adjust the IO parameters based on measurements, I think.
