TPS22967: ESD issue

Part Number: TPS22967

Hi there,

I'm having an issue with the TPS22967DSGR after an ESD discharge.

Here are the details of the ESD discharge:
+/-4kV conductive discharge on an exposed pad near the TPS22967;
using the NSG 435 ESD simulator set for a single discharge (IEC 61000-4-2 Level 2)

Although the issue doesn't always appear after the ESD discharge, the result is that the loads switch activates and the voltage on pin 3 (ON control logic) latches to 2.1V and stays there regardless on any input. The part resumes to normal behavior only after a power reset.

I've added extra ESD protection diode to that pin, but the behavior, although less frequent, still appears.

Do you have an idea of what could be causing this issue?

Best,

4 Replies

  • Hi Pedro,

    The TPS22967 is only rated for a maximum ESD strike of up to +/-2kV. Exceeding this rating may cause the device to get damaged, so +/-4kV strikes are not guaranteed. To protect the device, the ESD strikes need to be limited to +/-2kV.

    On another note, have you taken a look at the TPS22975? It is a next-gen version of the TPS22967 and gives better performance with added protection (thermal shutdown).

    Thanks,

    Alek Kaknevicius

  • In reply to Aleksandras_Kaknevicius:

    Hi Alek,

    Thank you for the quick response and suggestions.

    It looks like TPS22975 is also rated for +/-2kV. I'm considering using TPS22965-Q1 which, being Automotive grade, seems to provide better ESD performance (+/-4kV). Is the 2.1V "latching" on the ON pin something you'd expect as a result of an excessive ESD voltage discharge? Do you know of similar cases?

    This issue is time sensitive and I'm trying to understand if there is something else that could be causing this. Basically, I'm concerned I'm fixing the "symptom" instead of the "disease".

    If you have additional insight that would be very helpful.

    Thanks,

  • In reply to Pedro Silva91:

    Hi Pedro,

    Latching behavior can be a result of exceeding the ESD specifications in the datasheet, but I have not seen this specific behavior from this device.

    Is this system level ESD testing you are doing with the device? If so, please note that the ESD ratings for all of our load switches are based on the JEDEC standards specified in the datasheet. During this testing, the device is unpowered, and the ESD strikes are meant to emulate ESD strikes as a result of manufacturing, not system operation.

    Thanks,

    Alek Kaknevicius

  • In reply to Aleksandras_Kaknevicius:

    Hi Alek,

    You are correct. We are doing "system level" ESD testing with the device powered on and operating. I'll test the new loadswitch and see if the issue disappears.

    Thanks,