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tyassin's avatar
tyassin
Icon for New Contributor rankNew Contributor
1 month ago
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MAX10 (10M02SCU169I7G) - VREF pins

Hi,

I have a single supply device with 3.3V. I have to clarify my undestanding of the VREF pins.
They seem to have a dual purpose on this device:

  1. Can provide another reference voltage than the normal Bank voltage?
  2. Can be used as a normal IO?

Is this correct and if not used as a reference voltage or IO, should it be connected to anything?

Thank you.

Configuration
  • FvM's avatar
    FvM
    1 month ago

    Hi,

    VREF pins are used for voltage referenced I/O standards like SSTL, e.g. for DDR RAM. If not needed for this purpose, they are available as regular IO pins. Treat unused VREF pins like any unused IO, e.g. activate weak pull-up to avoid floating.

    Regards Frank

3 Replies

  • FvM's avatar
    FvM
    Icon for Super Contributor rankSuper Contributor
    1 month ago

    Hi,

    VREF pins are used for voltage referenced I/O standards like SSTL, e.g. for DDR RAM. If not needed for this purpose, they are available as regular IO pins. Treat unused VREF pins like any unused IO, e.g. activate weak pull-up to avoid floating.

    Regards Frank

  • tyassin's avatar
    tyassin
    Icon for New Contributor rankNew Contributor
    1 month ago

    I see. 
    Thank you very much for explaning.

    Br. Thomas

    • AqidAyman_Altera's avatar
      AqidAyman_Altera
      Icon for Regular Contributor rankRegular Contributor
      1 month ago

      Yes, Frank is correct. You can refer to the Pin Connection Guidelines for MAX 10.

      https://docs.altera.com/r/docs/683232/current/max-10-fpga-device-family-pin-connection-guidelines/differential-i/o-pins#:~:text=or%20GND.-,VREFB%3C%23%3EN0,-Power%2C%20I/O