• State Resolved
  • Locked Locked
  • Replies 6 replies
  • Subscribers 63 subscribers
  • Views 881 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.

TPS63020: Device operation latched in electrostatic test

Kaji@PAN
Mastermind 7795 points
Part Number: TPS63020

Hi,

I am conducting the electrostatic test on products with TPS63020 installed.
I attach the material (excel sheet) of the circuit I created.
On the input side of the TPS63020, there is a charger circuit and a fuel gauge circuit.
Both the battery and the 5V fixed power supply are input to the TPS63020 input.

Attach the waveform (Excel sheet) of TPS63020 when performing the electrostatic test.
When static electricity is applied, the operation of the TPS63020 is latched.
Even if EN is switched, the state does not change.
However, when shutting down the power supply, it returns to normal operation.

I want to ask you a question.
What is the cause of latching the operation of the TPS63020 device when static electricity is applied?

Best Regards,

TPS63020_20171215.xlsx

  • 0
    TI__Expert 8420 points
    Hi,

    Thanks for providing the schematic and the waveform. Could you be more precise on how is the electrostatic test is conducted?
    Does this happen in all devices? how many have been tested so far?
    Did you conduct the same test on a TPS63020EVM?

    What is the end application?
  • 0 in reply to Sabrina
    Mastermind 7795 points

    Thank you for your reply.
    The application is a shopping basket. The circuit attached to the shopping basket is loaded, and the circuit can read the bar code of the product.
    Since the battery is built in, it is necessary to supply electric power from outside to charge.
    When charging, 5 V is supplied from the outside to the "V5P0_INT" terminal of the attached circuit.
    Therefore, since this terminal goes out, probably there is a possibility that static electricity has invaded from this terminal.

    Creating 20 prototype machines, this symptom is occurring in half of them. Unfortunately, I have not tried it because I have not purchased it with EVM.

    Have you experienced symptoms like this in the past?

    Best Regards, 

  • 0 in reply to Kaji@PAN
    TI__Expert 8420 points

    Thanks the application details.
    I have not seen this problem before, I need discuss with our RnD team, to understand if there is an obvious reason in the design causing the latching.

    1. Can you describe if this test is performed , I will try to recreate the test conditions in the lab from my side
    2. Could you order a TPS63020 EVM and perform the same test?

  • 0 in reply to Sabrina
    Mastermind 7795 points
    Thank you for your reply.
    As additional information, yesterday, it turned out that the device of BQ 27520 in the attached diagram was destroyed.
    I am re-implementing the static test again now.
    So, if I could organize the information, again, I would like to ask you a question.
  • 0 in reply to Kaji@PAN
    TI__Expert 8420 points
    After discussing with our RnD team, I found out that a negative voltage on the EN pin can cause this latching, as it is connected to VIN . Maybe your electrostatic test circuit needs to be optimized to avoid this negative voltage on the pin.
  • 0 in reply to Sabrina
    Mastermind 7795 points

    Thank you for your reply.
    I really appreciate that.