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ISO7720: ABS MAX Vcc voltage (AC) for component

Part Number: ISO7720

My name is Dustin Braico and have a question about the absolute maximum voltage for Vcc. The datasheet shows 6V and im sure that only covers a DC level. Is there any information on how much energy or what level of spikes or ripple could be tolerated by the component?

We are driving the ISO7720FD with a 5V supply, but for short periods of time (<200mS every hour or so) another operation of our system generates some EMI which is picked up by the 5V line near the ISO7720FD. We've measured voltage spikes of up to 9V during that 200mS window. The spikes are approximately 10uS wide.

We would like to know what kind of tolerance the ISO7720FD has to those types of events and what might happen to the reliability of the part under those conditions. The part does not fail when the spikes are introduced so we would like to know if the amount of AC or spiking that is tolerable by the ISO7720FD has been characterized or if an engineer could elaborate on what might be tolerated by the component during those spiking conditions.

Thank you,

 

Dustin Braico

  • Hi Dustin,

    Welcome to TI E2E forum!

    The ISO7720 device has been characterized for DC supply voltages and we recommend device operation upto 5.5V but the device can withstand upto 6V of stress. Since we do not perform any specific voltage spike related characterization, we will not be able to guarantee any specific withstanding capability for any voltage spikes of specific duration.

    From our expectations point of view, any voltage >6V can have cumulative effect on device and can affect device reliability in the long-term. 9V for 200ms every hour could also affect reliability in the long-term.

    Do you see these spikes at VCC pin of ISO7720? Could you please share any waveform you have?
    The decoupling capacitor at the VCC pin might be able to filter that spike and bring it down. You can try increasing the capacitance to see if that suppresses the spike better.

    Look forward to the waveform, thanks.


    Regards,
    Koteshwar Rao

  • Hi Dustin,

    I hope your question is answered with my previous response. I will go ahead and mark this as closed. If you still need any further questions, please feel free to respond to this E2E post. Thanks.


    Regards,
    Koteshwar Rao