We designed several Adum3482 into a product and found to our surprise that the VDDL1 pin can power our entire board -- with current flowing out of pin 1.
Schematic fragment here.
All IO is 3.3V, and I assumed that the best way of using this was to run VDD from 5V, and the logic level translators from 3.3V. The problem is that I have approx 180mA flowing back out of pin 1, happening on multiple devices. Raising pin 1 to 5V corrects this -- obviously.
I did wonder if CTRL1 was part of the logic translator "domain" so I removed the 5V from there and drove it with 3.3V, no change.
There is a drop of approx 1.1V when supplying 180mA, so I suspect there is a diode involved. The device does get hot when supplying current.
Has anyone ever tried these devices with VDDL lower than VDD ?
This is an urgent request, volumes in 6 digits involved.