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Vigneswaran's avatar
Vigneswaran
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1 month ago

Agilex 7 Decoupling capacitor scaling factor

Hi!

I have got my power estimate from quartus prime based on our requirement, which is "  board's power consumption". Now to find the scaling factor i need to know the "maximum power per power rail" , where would i get this value? is it related to FPGA part(AGFB027R24C2I2V) or the max current rating of my convertors?

 

Thanks,

Vigneswaran

Power

5 Replies

  • Vigneswaran's avatar
    Vigneswaran
    Icon for New Contributor rankNew Contributor
    26 days ago

    Hi Farabi,

    Thank you for your reply.I have completed the 4steps you have mentioned.

    I am able to finalize my buck convertor designs with 30% margin. This is not a problem.

    I need to finalize the decoupling capacitor requirement.This is my problem statement.

    In Power distribution network, (as shared image) To finalize decoupling requirement it is said to use "SCALING FACTOR".

    To find scaling factor it is said,

    Scaling factor = Max power per rail / My requirement per rail(which i got from quartus)

    Now, What is Max power per rail that i have to substitute?

    Eg: for +0.9V, My req from quartus is 60A, so i have selected a buck for 100A. Now what is the scaling factor?

    Scaling factor= Max power per rail / 60

     

     

    Thanks,
    Vigneswaran

  • Vigneswaran's avatar
    Vigneswaran
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    1 month ago

    Hi Farabi,

    Thanks for your reply. I have doubt , the power consumption generated from Quartus , is power consumption of my logic, right? Then how i can take that value as a maximum power consumption of each supply rail. 

    In datasheet it mentioned , scaling factor is the ratio of board's power consumption to maximum power per rail. So , I got my board's power consumption value through Quartus software. Now I need the value for maximum power per rail. Where should I find the value? 

     

    Regards,
    Vigneswaran

    • Farabi's avatar
      Farabi
      Icon for Regular Contributor rankRegular Contributor
      29 days ago

      Hello Vigneswaran, 

       

      Let me explain more details:

      1- Power consumption is varies for each design. 

      2- When you compile your full design with Quartus, Quartus will generate power estimation for each power rails. 

      3- The report is in <design>.pwr.rpt 

      4- You will use this report as reference to design your power circuitry. 

       

      Please explain if this is NOT what you want. 

       

      regards,

      Farabi

       

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

    Hello, 

     

    If you have completed design compilation, Quartus will generate power report for your design. In this report, it will show details of each power rails. 

    design_folder > output_files > *.pow.rpt

     

    regards,

    Farabi