• State Resolved
  • Locked Locked
  • Replies 6 replies
  • Subscribers 31 subscribers
  • Views 948 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

AWR1642BOOST: audible noise

Ryuji
Guru 20090 points
Part Number: AWR1642BOOST
Other Parts Discussed in Thread: AWR1642, IWR1642

Hello,

There is the audible noise(pip-pip sounds) when we launched AWR1642BOOST and read the default command.
The audible noise frequency is varied when we change the frame rate. I think that the noise is synced with the frame rate.
We check the two BOOST boards(AWR1642 and IWR1642) and both EVM generate this noise.
Could you please let me know the cause of this sound? 

Please see the attached video as the sounds. You may not play this video but I think that you could check same sound your EVMs.

Best Regards,
Ryuji

  • 0
    TI__Guru 58035 points
    Hello Ryuji,
    We have not heard this kind of noise before. Could it be possible its coming from the power supply you are using? Could you try changing the 5V power source and checking it?

    Regards,
    Vivek
  • 0 in reply to Vivek Dham
    Guru 20090 points
    Hello Vilek san,

    We use 5V/3A AC adopter. And we change the 5V/4A AC adopter but we could hear the noise yet.
    According to user's guide, should we use 5A current limit AC adopter? Unfortunately, we don't have 5A AC adopter.

    Could you please check the noise again?
    The audible noise is very small.
    It is necessary to listen carefully by bringing the ear close to the board.

    Best Regards,
    Ryuji
  • 0 in reply to Shankar Ram
    Guru 20090 points
    Hi All,

    Thank you for the information.
    Firstly, I thought that the noise from inductor or capacitors.
    The 3.3V output of the LP87524 is operated in PFM mode. And the switching frequency in audible frequency.
    However, when we change the fps rate of AWR1624 the audible noise speed is changed. But the switching frequency is not changed.
    Then I touched on various parts of the board to see if the noise changed, but it did not change.
    I would like to know the noise source of the board.
    We can hear the audible noise with default conditions after read the command.(Not power on only.)

    Best Regards,
    Ryuji
  • 0 in reply to Ryuji
    Guru 20090 points

    Hi All,

    I'm sorry for bothering you but could you please let me know if there is any update on this topic?
    If the acoustic noise is occurred by AC adopter, could you please share the sample audio file ?
    Also, can you open the file my attached video?
    I want you to hear this sound once. I can send the file if you contact following my e-mail address.

    asaka-r@macnica.co.jp

    Best Regards,
    Ryuji

  • 0 in reply to Ryuji
    TI__Guru 58035 points
    Hello Ryuji,
    Apologize for the late reply. With careful analyses of your inputs we are able to hear the noise at our end also and it does seem to correlate to the frame rate. I did a bunch of experiments to rule out the source of the noise to be the power adapter, or the ferrite bead or diode at the supply input.
    It seems to be , as indicated in the article in the above post by Shankar, due to ceramic capacitors. After every frame the load current switches from a very high value during chirping to a very low value in the inter frame time. This could be causing the noise at the frame rate.

    Regards,
    Vivek