Yes, the EN1 and EN2 refresh/watchdog enable pins must be set to the same state for the ADuM144x to operate properly.
The ADuM144x family contains a glitch filter to reject narrow pulses at the input. The glitch filter width is dependent on the input supply value, and ranges from 100 us at 2.3V to 50 us at 3.6V. Refer to the data sheet for a typical characteristic…
The receiver watchdog times out after approximately 200 us.
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