For our design we do need to slow down the start up of the Refout voltage.
To do so we wanted to put a slow start over the Refout pin as a RC circuit (R= 10kOhms and C = 1µF). With the resistor directly connected to REFOUT and the capacitor connected to GND2.
We would like to know if the 10k resistor is enough to keep the margin over the buffer on the REFOUT pin.
Hello Maxime - can you indicate which product you're asking about? IS it the ADuM3190/ADuM4190?
Yes it is the ADuM3190
I think that should work. Can you describe your application or show a circuit with the ADuM3190?
Hello Brian, please find attached the schematic of the ADUM in my application.
I used the component to regulate a Flyback converter over a 3.3V winding and the ADUM is supplied by the 5V winding of my flyback.
So, my IN- is the 3V3 winding through a resistor bridge. And the IN+ is connected to the REFOUT.
I tried to use the simulation model provided but the implementation of the REFOUT in the model does not seem to correspond exactly with the component behaviour.
Is it possible to have a more precise model to measure our phase and gain margin with this schematic ?
Maxime: We have a newer LT Spice model for the ADuM3190 that I can send you by email - you can click on my icon and email me.