• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 2 answers
  • Subscribers 31 subscribers
  • Views 1132 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.

TPA3110D2: EMI failed

Jerry Hsueh
Expert 2730 points
Part Number: TPA3110D2


Hi TI

When we do the EMI testing.

The conduction test was failed at the three green points shown in the following figure.

Do you have any suggestions for improvement?

Thank you.

Jerry

  • 0
    TI__Expert 6295 points
    hello,

    what is switching frequency select for your case? is there power supply have EMI filter design?

    Regards
    Linda
  • 0 in reply to Xiaolin Qin
    Expert 2730 points
    Hi Linda,

    Switching frequency is about 300KHz. LC filters are added to the power input and TPA3110D2 output.

    Thanks,
    Jerry
  • 0 in reply to Jerry Hsueh
    TI__Genius 9995 points
    Hi Jerry,

    Firstly, please keep your board is good grounded with LSIN. Then please update your measurement details with us, eg. output power, PVDD， Speaker load=？ohm etc.

    Based on your report, it is strange to see that 3th harmonic is larger than primary tone @ ~300KHz. It is not reasonable on my side. Please check:
    1. please check your power board by changing another power board or adapter to see whether it is caused by different suppression capability of power board at 300KHz and 900KHz;
    2. Tuning your EMI filter by adjust inductor and cap to see whether it can be lowered ;
    3. Please check our inductor to see whether it is saturation that cause this.

    Regards,
    Alix Wan