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BrianSune_Froum's avatar
BrianSune_Froum
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29 days ago

Cyclone IV drop in replacement confirmations

Dear Altera, If the BANK VCCIO is 1.8V and the same package but with different LE # FPGA is drop in replace. Where the original pin is a VCCA while different LE size same pin is a IO. With 1.8V on...
Generic Io
Power
Programmable Logic Device
AqidAyman_Altera's avatar
AqidAyman_Altera
Icon for Regular Contributor rankRegular Contributor
24 days ago

Hi Brian,

 

Can you provide the OPN for both of the devices that you refer here?

 

Regards,

Aqid

BrianSune_Froum's avatar
BrianSune_Froum
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24 days ago

AqidAyman_Altera​ 

The question is not related to any specific Cyclone IV devices:

The question is about when VCCIO is driven from 1.8V or any voltage under the VCCA, do the input pins are allow to feed in 2.5V or 3.3V as datasheet marked with <3.6V on inputs?

When this question is answered there is no issue on the remains drop-in compatibilities.

Thanks,

Brian

 

  • AqidAyman_Altera's avatar
    AqidAyman_Altera
    Icon for Regular Contributor rankRegular Contributor
    15 days ago

    Hi Brian,

     

    These two devices should not be treated as drop-in replacements in this board condition. Cyclone IV supports vertical migration within the same package, but the migration devices must have compatible dedicated input pins, configuration pins, and power pins.

     

    You can select migration devices in Quartus and check the Pin Migration view for pins whose functions change. The Fitter uses the selected migration-device list to restrict the design to compatible pins; pins that are power pins on one device should not be treated as usable user I/O across the migration path. 

     

    Reference: Device Migration Planning, AN 592: Cyclone IV Design Guidelines.

     

    Maybe just for your information, I saw an old documentation, Quartus® II Handbook mentioning below statement:

     

     

    Regards,
    Aqid

    • BrianSune_Froum's avatar
      BrianSune_Froum
      Icon for Contributor rankContributor
      15 days ago

      AqidAyman_Altera​ 

      The table I attached is from the "Pin Migration view".

      Yes datasheet Larger die -> smaller die migrate.

      Which is understandable from the idea of 1.8V / 1.5V VCCIO minimum requirements so 1.2Vcore/GND is always treaded as input / HI-Z and does not contradicts the voltage requirements.

      But the issue we are discussing is VCCA in that table which larger die have more PLL power pins.
      So drop-in migration have no clear details on such.

      3.6V is maximum input but VCCIO aka 1.8V vs 2.5Vcca fixed power pin require Altera to response the proper drop-in design/treatment.

      Thanks,

      Brian