• Resolved

ISO7641FM: 6000V Vpk test failed in customer test

Part Number: ISO7641FM

My customer tested the ISO7641FM isolation voltage, by applying short-time(1.2/50 us) peak voltage(6000V) pulse between isolation barrier both sides. 4pcs were found damanged and only 2pcs passed the test. Below is test method(each side pins are all shorted) and applied voltage pulse.  ISO7641 spec can sustain 6000V peak for 1minutes. So please check what's reason. Thanks.

  • Hi Garrick,

    I am sorry to know that your customer had issues in testing ISO7641FM for 6kV surge test (1.2/50µs). We do expect ISO7641FM to pass 6kV surge test and this device has been sufficiently tested for the same.

    The test waveform that you have shared looks quite different from a typical surge pulse,

    1. Could you please share more details about the kind of pulse that customer had applied?
    2. Do you know how many pulses were applied to each sample?
    3. Do you know if both positive and negative pulses were applied? If yes, how many?
    4. Do you know what was the fail signature observed on ISO7641FM? Did the impedance across barrier go down?

    Please do share the above information so that we can help find out why the device failed 6kV surge test?

    If customer is evaluating ISO7641FM to be used in their product in development, I would suggest recommending customer to use ISO7741 instead. ISO7741 would support at least 12.8kV of surge performance along with many other benefits that are clearly evident from the datasheet. Thanks.


    Regards,
    Koteshwar Rao

  • In reply to Koteshwar Rao:

    Hi Rao,

    Please find below. Actually customer do such test from 3KV to 4KV, 5KV, 5.5KV and 6KV. ISO7641 can survive till 5.5KV, as below left waveform. But when do 6KV test, the device broken and voltge waveform like below right(maybe the scope cannot capture the peak waveform, so just show 3KV and down). Do you think this is related to application issue or quality issue?

    1. Could you please share more details about the kind of pulse that customer had applied?
    2. Do you know how many pulses were applied to each sample? =>One test just use one pulse. Will repeat three times for each voltage level;

    3. Do you know if both positive and negative pulses were applied? If yes, how many?=> Only use positive pulse.  One pulse per time;

     4. Do you know what was the fail signature observed on ISO7641FM? Did the impedance across barrier go down?=>The device/chip surface broken(raised);

  • In reply to Garrick Dai:

    Hi Garrick,

    Thank you for your details and waveforms. My apologies for the delayed response; our isolation team is still investigating this and will follow up by Friday.


    Respectfully,
    Manuel Chavez
  • In reply to Manuel Chavez:

    Hi Garrick!

    Hopefully you're doing well. Do you know the Lot Trace Codes of your devices? These are letters and numbers written on the top face. We will need them for further debug to help determine the root cause.


    Thank you for your patience with us,

    Manuel Chavez
  • In reply to Manuel Chavez:

    All,

    This thread is currently being resolved via email. Garrick or myself will respond once the solution is found. For similar questions or concerns please feel free to ask a related or new question using the buttons on the top right corner of this window.


    Best,
    Manuel Chavez