• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 1 answer
  • Subscribers 13 subscribers
  • Views 333 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

ISOW7841: Improve EMI emissions noise

Shuji Ishiwata
Mastermind 7065 points
Part Number: ISOW7841
Other Parts Discussed in Thread: UCC33410, ISO7741, ISOW7741

Tool/software:

Hi All,


I have a question about the ISOW7841.
I would like to improve EMI emissions noise.
Are there any other solutions besides improving the board layout?

I am also considering using the UCC33410 and ISO7741 in a similar way to the ISOW7841.
Will the UCC33410 and ISO7741 generate the same amount of EMI emissions noise as the ISOW7841?


Best Regards,
Ishiwata

  • 0
    TI__Guru 55575 points

    Hi Ishiwata-san,

    Thank you for reaching out.

    Do you know if customer has already made PCBs using ISOW7841 and tested for radiated emissions? If yes, then I would like to review the design and emissions test results before I make any suggestions.

    If this is for a new design, then I recommend considering our second-generation device ISOW7741 which offers significantly higher overall performance and meets radiated emissions using a simple design.

    Both UCC33410 and ISOW devices integrate isolated DC-DC converter in a small package and switch at high frequency. Due to this, it is important to follow the design and PCB layout guidelines to meet radiated emissions requirements. Thanks.


    Regards,
    Koteshwar Rao

  • 0 in reply to Koteshwar Rao
    Mastermind 7065 points

    Hi Koteshwar-san,

    Thanks for your reply.

    EMI test results have been requested for the customer.
    Please wait.

    Best Regards,
    Ishiwata

  • 0 in reply to Shuji Ishiwata
    Mastermind 7065 points

    Hi Koteshwar-san,


    I have received the ISOW7841 EMI test results.
    I received the EMI test results from the customer, so I will send it to you via private message.
    Can I send you a friend request?


    Also, the E2E below states that adding chokes can improve the situation.
    e2e.ti.com/.../3108951

    Where should I place the chokes to be effective?


    Best Regards,
    Ishiwata

  • +1 in reply to Shuji Ishiwata
    TI__Guru 55575 points

    Hi Ishiwata-san,

    Yes, I have sent you a friend request. You can accept the request and send me the EMI test results. Please also send me customer schematic to review for any issues.

    Yes, using common-mode chokes (CMC) at the input and output power supply pins of ISOW7841 can filter the radiation noise and keep the emissions to minimal. Please take a look at the below E2E post for more details related to CMC suggestion. Thanks.

    https://e2e.ti.com/support/isolation-group/isolation/f/isolation-forum/806938/isow7841evm-isow7841evm


    Regards,
    Koteshwar Rao

  • 0 in reply to Koteshwar Rao
    Mastermind 7065 points

    Hi Koteshwar-san,

    I really appreciate your support in the private message. 

    Best Regards,
    Ishiwata