• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 645 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.

TPS25921A: Ask about short-circuit protection

Masazumi Ishii
Genius 3945 points
Part Number: TPS25921A

Hello.

I have a question about TPS 25921.

For details, please see the attached document.

Thank you for your consideration.
Microsoft PowerPoint - TPS25921.pdf
  • 0
    TI__Guru* 95911 points
    Hi Ishii,

    I will look into the test waveforms and get back to you shortly.

    Best Regards,
    Rakesh
  • 0 in reply to Rakesh
    TI__Guru* 95911 points
    Hi Ishii,

    I hope you are making a wire-loop to measure current. It is going to add inductance and generate negative spikes at the output during short circuit. The second current spike is probably due to the inductive kick-back voltage driving current through the device ESD diode.
    I see Vout going to -2.5V in the second waveform. This will exceed the Absolute Maximum Ratings of the device. Please refer Section 11 in the datasheet and place Schottky diode across the output of the device.

    Best Regards,
    Rakesh
  • 0 in reply to Rakesh
    Genius 3945 points
    Hello.

    thank you for your reply.
    As you can see from the e-mail, when we short-circuited the output with a small loop, the second large current and the negative voltage fluctuation of the output voltage disappeared.
    It is an additional question.
    The current that can flow with DC of FET is 1.6 A (MAX), but how much current can be pulsed?

    Thank you.
  • 0 in reply to Masazumi Ishii
    TI__Guru* 95911 points
    Hi Ishii,

    Nice to know about that.

    The internal fast-trip circuit restricts the max. allowable pulsed current and cuts-off the path in 3us (typical). For example, when the current limit is set at 1.6A, the fast-trip threshold will be at 2.5A, considering the delays the possible pulsed current will be <5A only. As it is very short internal operation, there will not be any issue to the device.

    Best Regards,
    Rakesh