Can help to advise if the ADUM3400 can be replaced by the ADUM140E?
What happen if we leave the Pin 7 of ADUM140E to NC?
Generally yes, the ADuM140E in 16L-SOIC_W can replace the ADuM3400. The devices are different and the datasheet specifications should be evaluated for the specific application needs.
Pin 7 of the ADuM140E…
Pin 7 of the ADuM140E has no internal connection.