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Altera_Forum's avatar
Altera_Forum
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15 years ago

can open-drain output bear voltage of 5V?

Hi there,

I want to use 5V output but cyclone ii device does not support the 5V IO standard. I know that cyclone ii device can configed as open-drain outputs, can I pull the OD ports up to 5V? Is there any risk to the FPGA device?

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    How about using MAXII to exchange voltage.

    Input 3.3v in MAX II and out as 5.0v from it.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

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    Is there any risk to the FPGA device?

    --- Quote End ---

    You shouldn't do that, it's clearly beyond maximum ratings. You should at least implement PCI clamp diodes for the respective outputs.