• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 64 subscribers
  • Views 178 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.

TPS22968: Why do TPS22968 have second conduction when power down?

Wiky Liao
Intellectual 1810 points
Part Number: TPS22968

Hi Team,

Our customer connect BIAS to VIN, which is normally 3.3V. When doing power down test, after detect Vin lower than 2.5V, ON pin will set to LOW to disconnect the circuit, so BIAS will lower than 2.5V during the test. But we find a second conduction of the load switch, could you help to comments why TPS22968 have this behavior? Thanks.

Blue: VIN

Green: Vout

Pink: ON.

time data between first disconnect and second conduction: 127ms.

  • +1
    TI__Mastermind 32650 points

    Hi Wiky,

    What is the voltage of the ON pin during this second conduction? From the waveform it looks to be over V_il but under V_ih.

    Could you please add some sort of pull down resistor to this ON pin node so that the voltage will discharge to 0V as soon as it is OFF?

    Thanks,

    Shreyas

  • 0 in reply to Shreyas Dmello
    TI__Intellectual 1810 points

    Hi Shreyas,

    Thanks the comments and pointing out the ON pin voltage. I think it is the root cause. I will let customer add pull down resistance and re-test.