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ANBARASU's avatar
ANBARASU
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1 year ago

CYCLONE V FPGA POWER-UP SEQUENCE

Currently i am using the below cyclone V FPGA for my design, Part: 5CGTFD7D5F27I7N As per the CV-52001 (2023.10.18) -Volume 1: Device Interfaces and Integration The recommended power-up sequence g...
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Farabi's avatar
Farabi
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1 year ago

Hello,


You need to make sure all the power rails in Group 1 ramped up to their own voltages first, then you can ramp the other power rails in Group 2.


Within Group 2, there is no sequence, you may ramp up VCCPGM first then VCCIO etc , as long as you already completed all Group 1 ramp up.


Notes : each power supplies must be ramped up within the given tRAMP time, which is <100ms for standard POR and <4ms for fast POR. Difference between Standard POR and Fast POR is the POR delay timing(this is not controlled by users). Users can only set in MSEL.


regards,

Farabi



ANBARASU's avatar
ANBARASU
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1 year ago

Hi Farbi,

As above mentioned, there is no sequence order required in group 2, But i could see the below statement.

Here i am using Bank 3B/4A and Bank 7A/8A uses VCCIO as 1.35V and VCCPD as +2.5V.

These 2 bank voltages alone i am using VCCIO and VCCPD as different voltages, other bank voltages either 3.3V or +2.5V for both VCCIO and VCCPD are same.

Query:

If i understood correctly if i enable 3.3V first in the group 2 and followed by +2.5V/1.35V together i will meet the NOTE 35 point. Please confirm.

  • Farabi's avatar
    Farabi
    Icon for Regular Contributor rankRegular Contributor
    1 year ago

    Hello,

    Please make sure you follow this pin connection guideline, link : https://cdrdv2-public.intel.com/654351/pcg-01014.pdf

    1. If you have same VCCIO voltage with VCCPD, you may connect the power rail to the same voltage regulator and power up together.

    2. If you have VCCIO less than 2.5V, for eg. you connect VCCIO to 1.35V, VCCPD located in the same IO bank must be supplied by 2.5V. For this case, you need to power VCCPD 2.5V first, followed by VCCIO 1.35V to avoid current transient.

    Back to your question: "If i understood correctly if i enable 3.3V first in the group 2 and followed by +2.5V/1.35V together i will meet the NOTE 35 point. "

    <ANS> Yes, correct.

    regards,

    Farabi

    • ANBARASU's avatar
      ANBARASU
      Icon for New Contributor rankNew Contributor
      1 year ago

      Hi Farabi,

      Thank you! But i could see some difference from the user guide,

      User Guide:

      It says if the VCCIO and VCCPD requested to powering up together,

      Response:

      2. If you have VCCIO less than 2.5V, for eg. you connect VCCIO to 1.35V, VCCPD located in the same IO bank must be supplied by 2.5V. For this case, you need to power VCCPD 2.5V first, followed by VCCIO 1.35V to avoid current transient.

      You are requesting to power up VCCPD first followed by VCCIO.

      Please confirm which one is correct?

      Regards,

      Anbarasu S