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ISO7740: Noise Immunity at high frequency

Part Number: ISO7740

To whom it may concern

Our customer is concern about radiation and conduction noise at high frequency against malfunction of digital isolator.

For op amp, parameter is specified as EMIRR that is immunity against noise at high frequency these day.

In the case of digital isolator, are there similar parameter like EMIRR ?
If no, could you provide any data against immunity against noise ?

Your reply would be appreciated.
Thanks and best regards.

  • Hi,

    The parameter we have related to immunity is CMTI (Common Mode Transient Immunity).
    But this specification talks about the immunity against noise in GND1 with respect to GND2. ISO7740 can handle 100kV/us (typical) common mode transients.

    Since radiated emissions and conducted emissions are system level specifications, we don't specify them in the datasheet.
    However we have done radiated immunity testing on ISO7740 using our EVM according to the IEC61000-4-3 standard and have observed it passing till 30V/m with antenna at a distance of 1m from DUT (Level 4).

    Since these test results will heavily dependent on the system. Could you please let me know what testing is being performed, what is being expected and if possible some details about the end equipment or application?
    Thank you.