• State TI Thinks Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 317 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.

TPS54620: SS/TR being pulled low before PG falling?

Allen Wachter
Expert 6730 points
Part Number: TPS54620

For the TPS54620 what are the conditions which would cause SS/TR to be pulled low prior to PG? 

The SS/TR pin is connected to a voltage divider which remains steady during this event.  The divider voltage at SS/TR is 1.5V.  

Thanks,
Allen

  • 0
    TI__Mastermind 35185 points

    Hi Allen,

    There are two scenarios I can think of below. Based on these thoughts it would be interesting to repeat this test while monitoring COMP and EN.

    1. The overload recovery circuit is pulling down as a result of the COMP pin hitting its clamp voltage. The cases I can think of where this would happen is if the part is operating in current limit or the input voltage is too low to regulate the output voltage. When the COMP pin hits the clamp voltage, this circuit will pull down the SS/TR to near the VSENSE voltage. If I remember right the COMP clamp voltage is around 1.8 V for this part.
    2. Perhaps there is a glitch on the EN pin causing it to go low then high again very quickly. The time it is low is long enough to cause the SS/TR pin to reset but not long enough for the PWRGD pin to pull low. However this is just a guess. I don't know if this actually possible to happen.

    Best Regards,
    Anthony

  • 0 in reply to Anthony F
    TI__Mastermind 35185 points

    Closing this E2E post because we have moved the discussion to e-mail.