• Resolved

AFE5809EVM: AFE5809EVM Digital Demodulator

Part Number: AFE5809EVM

Hello,

I am trying to use AFE5809EVM Demodulator feature.

1.  If possible, Can you guys please help me to design filter for 40/32 = 1.25 MHz ?

2. If possible I would like to set filter cut-off freq to 350 KHz.

Please let me know if you need any further information.

Thank you.

  • Hello Vatsal,

    We will look into this and provide details by May 16th.

    Best Regards


    Praveen Aroul

  • In reply to Praveen Aroul:

    Hi Praveen,

    Thank you.  Also, I would like to know this, How to set Down conversion frequency in GUI ? I can see there is a manual frequency EN for downconversion.

    Can you please tell me how to set it to 300KHz ? I found some information in Data-sheet but not sure how to use it.

    Thank you.

  • In reply to Naik:

    Hi Praveen,

    Any updates yet? thank you.
  • In reply to Naik:

    Hello Praveen,

    I am wondering that do you have any progress yet?
    Thanks.
  • In reply to Naik:

    Hello TI people,

    Any progress yet?

    Thanks
  • In reply to Naik:

    Hi Vatsal,

    I believe the reason for the problems using the digital demodulator on the AFE5809EVM GUI is an MSB/LSB mismatch between HSDC Pro GUI and the AFE5809EVM GUI.

    The user guide needs to be updated to reflect this. Unfortunately, I won't get around to taking an in-depth look at it until maybe the end of next week.

    We apologize for the delay and appreciate your patience.

    Sincerely,

    Olu

  • In reply to Olu Sodipe:

    Hi Olu,

    Thank you for your reply. Let me know when you have any updates.

    Thanks.
  • In reply to Naik:

    Hi Vatsal,

    Thank you for your patience. Please answer the following questions so we can correctly address your problem.

    Have you been able to successfully get the default demodulation features outlined in the user guide working using the AFE5809 board?
    Furthermore, what do the numbers '40' and '32' refer to when you mention '40/32 = 1.25 MHz'?

    Sincerely,
    Sahana
  • In reply to Sahana Krishnan:

    Hi Sahana,

    My requirement changed since. Now We are using the 20MHz clock for AFE5809. So I am looking to configure profile RAM and coefficient RAM for that.

    1.) I am looking to Downconvert with 350KHz. So I am using register for that. In GUI Manual_Freq_EN = 1 and Manual_Freq = 47B, which gives me almost 350KHz mixing frequency for downconversion. Is this the correct way to do it?

          1.A)  Also, Is there a way that I can only get In Phase information from downconversion? I don't need Q.

    2.) I want to decimate with 32. My Fs = 20MHz so after decimation I will get Fs= 20MHz/32 = 625KHz. So for that, I need low pass filter coefficients for a coefficient vector. ( I am looking for 0 to 300KHz passband for the filter).

    3.) What is the Demod Freq window in GUI? just above the Fs. please see attached screenshot.

    4.) I have attached a screenshot for GUI setting that I'm trying please let me know if you have any questions. 

    Please let me know If you have any questions. 

    Thank you,

    Vatsal

  • In reply to Naik:

    Hi Vatsal,

    We are working on getting your issues resolved but I had some questions!

    1) There is a formula in the data sheet that reads: (N*Fs)/2^16. This formula can be used to calculate the oscillator frequency. Is the oscillator frequency what you want to change and set to 350 kHz? Using this formula, I would also like to know what numbers you are putting in for both N and Fs.

    Sincerely,
    Sahana