• State
  • Locked Locked
  • Replies 5 replies
  • Subscribers 30 subscribers
  • Views 620 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.

TAS5731M EVM Intermittent operation of the output

yoshiki hasebe
Mastermind 6385 points
Other Parts Discussed in Thread: TAS5731M, TAS5707

Dear Sirs,

My customer asked me urgent  intermittent operation of the output  when using EVM.

Intermittent time(off time) is about 300ms.

Setting condition is

1.PVCC:16.4V Vin:5V　

2.Input Signal:400Hz Full scale (optical input)

3.Output power 26W(4Ω）

4.Check the output of normal in this state.

5.Then change input signal to Music Source(Level large source of (those FullScale level there are many))

Intermittent operation occurs when you check in this situation.

Could you please tell me advice or information until this weekend.

Also I have some questions.

Because I think  Overcurrent Protection is working.

Specification of IOC( Overcurrent limit protection) is 4.5A at typical value.

Please tell me below questions.

1.Detection location of  Ioc.

2.Method of detecting(measuring) Ioc.

Best Regards,

Y.Hasebe

  • 0
    Guru 36540 points
    Hi Hasebe-san,
    As you said, I believe that TAS5731M will set the power stage to Hi-Z if detecting the overcurrent since it does not have a cycle-by-cycle current-limiting function like TAS5707.
    So, please refer to "9.3.4.1 Overcurrent (OC) Protection With Current Limiting" which is mentioned on page 25 of the data sheet.
    Then, for the recovery time, please refer to "9.6.15 BKND_ERR Register(0x1C)" which is mentioned on page 53 of the data sheet.
    Best regards,
    Kato
  • 0 in reply to Sadanori Kato
    Mastermind 6385 points
    Hi Kato-san,

    Thank you for your advice.
    I understand .
    But I do not know is why has occurred.
    Not occur in continuous wave, it has occurred in MusicSource.
    Moreover, it does not exceed the specifications of the Ioc.
    I want to know the possible causes and workarounds.

    Best Regards,
    Y.Hasebe
  • 0 in reply to yoshiki hasebe
    Guru 36540 points

    Hi Hasebe-san,

    Have you observed the pwm output, the inductor current and the output voltage after the LC filter when detecting the overcurrent ?
    In addition, please input the tone of the high frequency(e.g. : 10kHz/15kHz/20kHz full scale).

    Best regards,
    Kato

  • 0 in reply to Sadanori Kato
    Mastermind 6385 points

    Hi Kato-san,

    Thank you for your reply.

    I had observed output after the LC filter only.

    I will check inductor current and also high freq. input.

    Best Regards,

    Y.Hasebe

  • 0 in reply to yoshiki hasebe
    TI__Guru 57800 points

    Thanks for your help with this issue Kato-san!

    Hasebe-San,

    As Kato-san mentions, you need to measure the current at those points and verify any possible high frequency ripple current that could be triggering the OCP. 

    Regards,

      -Diego Meléndez López
       Audio Applications Engineer