Common Mode Transient Immunity (CMTI) is one of the key parameters to specify the ability of a Digital Isolator to reject the fast transient noise signals in data transmission.
CMTI is mostly measured in V/µs, by applying a transient between the ground at each side of the isolator. At a high slew rate, these transients can corrupt data transmission across the isolation barrier. Please note that higher CMTI indicates an isolator with a robust isolation channel - higher numbers are better, in this case.
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