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BrianSune_Froum's avatar
BrianSune_Froum
Icon for Contributor rankContributor
4 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 VCCIO and input fixed to VCCA aka 2.5V do this introduce any issue?

As we can see the datasheet mentioned the DC input accept 3.6 or below.
-> Table 1–4. Recommended Operating Conditions for Cyclone IV GX Devices (Part 2 of 2)

So the C4 device have a protection forward diode to clamp the voltage when IO is set to input?
As long as that pin is fixed to input state do this condition function properly?

Thanks,
Brian

 

Generic Io
Power
Programmable Logic Device

2 Replies

  • AqidAyman_Altera's avatar
    AqidAyman_Altera
    Icon for Regular Contributor rankRegular Contributor
    1 hour 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
      Icon for Contributor rankContributor
      32 seconds 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