Using Digital isolators instead of Opticouplers

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I've used them for digital bus/control signal isoation in a strain gage amp, seem OK so far but I've not started testing EMI performance

read the app notes carefully, these do use magnetic coupling so it's possible putting them in a really bad spot could be problematic in a SMPS - know where your sw currents flow, and how far your magnetic component leakage fields reach
 
Hi
I have used them to pass the PWM signal (PWM controller placed on secondary side) over the isolation barrier to driver circuit.
What I noticed is that at start-up when input side has an undefined supply voltage level (around 2 - 2.5V), the output generates some narrow pulses.
Those pulses can trigger your logics if, for example, such a digital isolator is used on a fault line.
It was the case of ADUM1100 but the manufacturer knows that behavior and I think they solved the problem by now (it happens about 2 years ago).
 
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