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Altera_Forum's avatar
Altera_Forum
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14 years ago

How to disable vrefb pins in quartus?

Hello All,

I have routed a 3.3v to VREFB1N0 in cyclone IV.

However,now,I am no longer needed that voltage reference.

So,should I disable the voltage reference pins?

If yes,how can I do it?By changing that pin to output pins?

Hope to hear from any of you sooner.

Thanks

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    The questions seems to be based on wrong assumptions.

    The VREF pins are used for voltage referenced I/O standards like SSTL with DDR RAM. Their function is automatic and don't need specific assignments (of course, they must not be configured as outputs when used as a reference input). Unused Vref pins are treated similar to unused regular I/Os, sharing the global unused pin policy.

    I can't imagine a reason to connect Vref to 3.3V.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    14 years ago

    Thanks for the explanation. To be frank, I was connecting the vref wrongly and somehow that bank does not working as expected(leds connected to that particular bank light up when they are supposed not to be)

    That's why I was wondering if it has

    something to do with the wrong voltage assignment on that bank vref