• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 13 subscribers
  • Views 421 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.

ISO7810: ABS MAX ratings at Transient

Hideki Hayashi1
Expert 8380 points
Part Number: ISO7810

Hi team,

Customer wonder ABS ratings, datasheet show input voltage is Vcc+0.5V max. But it is inconsistency with surge event. ISO7810 can protect communication from surge, this means ISO7810 can endure to surge event. So input voltage sometimes become very large voltage.

What can you explain about the reason why ABS max is Vcc+0.5V? How long does Vcc+0.5V last before destruction occurs? Or do I misunderstood differential voltage and common-mode voltage?

Best regards,

Hideki

  • 0
    TI__Guru 55795 points

    Hi Hayashi-san,

    Thanks for reaching out to us.

    The surge and other isolation ratings are the capability of the isolation barrier in ISO7810. The isolation barrier sits between Side1 (VCC1 side) and Side2 (VCC2 side), hence, these ratings apply to the voltages applied between Side1 and Side2.

    For example, you can apply upto 12.8kV of surge between GND1 and GND2 and there won't be any damage to device as the isolation barrier is rated for that. Similarly, ISO7810 in DW package supports a working voltage of 1500Vrms which means that you can apply 1500Vrms between GND1 and GND2 for >40 years and the device won't be damaged.

    The VCC and I/O pins of ISO7810 are logic pins just like any other digital device, hence, they can only withstand the abs max ratings provided in the datasheet with respect to their local GND. Most applications also do not require any surge related protection on logic I/Os, such protection are only needed on external terminals like RS-485, CAN or other interfaces. You can either use TVS diodes to protect these terminals from surge or isolate the system with separate GNDs so that the isolator protects the overall system GND with external noises.

    I hope the above explanation clarifies the difference logic I/O and isolation barrier ratings. Thanks.


    Regards,
    Koteshwar Rao