• State TI Thinks Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 381 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.

TPS54561 - reverse current -

Christoph Klees
Prodigy 220 points
Other Parts Discussed in Thread: TPS54561

Hy,

I use two TPS54561 parallel and it works very well.

No I have a question regarding reverse current through the TPS.

Both TPS54561 has different Input voltages, so it is possible that one Input voltage is 0V while the other is aviable.

In this case a reverse current flows from the Output to the Input of theTPS54561 to charge the Input capacitors.

Is this case allowed ro do I have to protect the device ?

 

Kind regards,

Christoph

 

  • 0
    TI__Guru**** 191445 points
    I general you should not operate TPS54561 in parallel. there is no guarantee of proper current sharing. In your case, if the output voltage is greater than one diode drop above Vin, then the body diode of the high side FET can conduct and some portion of the output will appear at the input. This is not a problem so long as the input voltage does not rise above the UVLO set point. You do not want the device to turn on in this circumstance.
  • 0 in reply to JohnTucker
    Prodigy 220 points
    I don't want to share the current, both supplies have the ability to source the electronic alone.
    I only have to guarantee that, in fact of a failure, the second supply is able to source the electronic.
    The voltage that is reverse injected does not rise above the UVLO.
    I'm only afraid of the reverse current, but it seems, if I understand you, no problem for the FET.

    Christoph