We're testing a new system with on board digital isolators. ADUM144x datasheet (http://www.analog.com/media/en/technical-documentation/data-sheets/ADuM1440_1441_1442_1445_1446_1447.pdf) specifies an absolute maximum rating for Vdd1 and Vdd2 of +5V.
There are two sections with recommended Vdd1 and Vdd2 (2.5/3.3V), but we were not able to find a maximum long term acceptable voltage.
Our application is quite unusual, and we're testing our prototypes with both Vdd1 and Vdd2 <= 4.0V (typically between 3.6 and 3.9V). We cannot use a system voltage with higher stability, and lowering the maximum operating voltage is tricky. The prototypes, after a few hours of testing, are working exactly as expected. However, we need to be confident about long term reliability in industrial environmnent, after product approval and product series have been installed.
Can you confirm if an operating voltage <= 4V could impact functionality of the device?
Thank you for your support.