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Altera_Forum's avatar
Altera_Forum
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16 years ago

open-drain/open collector type of output

Hi All, This might have been discussed before, but I didn't see a definite answer. I have one IO pins which I wanna assign it to be a open-drain type. I tried to add the following attribute ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

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The open-drain configuration is required to allow the pin to sink current.

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Sorry, I don't get why you would need a specific dedicated IOE configuration for that purpose.

If the data output at the IOE is permanently tied to ground, and the original data signal is negated and then used as Output Enable, then you effectively has an open drain output.