• Resolved

ISO7741: Impact of output voltage with CMTI standard in Datasheet

Part Number: ISO7741

Hi Expert,

For ISO77xx series, the standard for passing CMTI is "The output must remain stable". 

What is the value of voltage variation what we treat "output" of ISO77 is stable? The output must be less than what value so that we think it pass 85kV/us CMTI.

Thanks.

Zhou

  • Hi Zhou,

    I am not sure if I understood your question completely. Are you asking how much of OUT pin voltage variation can be treated as PASS and how much as FAIL?
    Since OUT pin supports only digital data, a state change at the OUT pin due to common-mode transients is counted as CMTI fail. Since most of the blocks inside device are digital in nature, common-mode transients can generally cause a state change anywhere in the channel from HIGH to LOW or LOW to HIGH. They generally do not cause any voltage variation at the output pin directly. Like it is mentioned in the image you have shared from datasheet, OUT can be either VOH or VOL and a CMTI fail would mean change over from VOH to VOL or VOL to VOH.

    Let me know if this answers your question. Thanks.


    Regards,
    Koteshwar Rao