I am currently designing a product which will use the ADUM2250 to isolate across Live 230Vac mains and will need to comply with EN60065 as a Class1 product
I am trying to asses what I need to do about the safety limiting vaues and it seems confusing, starting with the values
1. The datasheet table6 says "supply current, IDD1 + IDD2, 550mA" but the graph plot says Idd1 only.
2. Your VDE document (VDE-0884-10-2019-3-19.pdf) says Max input current 265mA, and max output power dissipation 900mW.
Values aside, it seems to me that I have to put a resistor in series with the VDD1 and VDD2 pins to limit the current. (with a suitable bypass capacitor of course)
Lets say that I think I need 100R and the Vdd is 5V. That means I may have onltl 4.5V on the IC. I know that it works fine to 3V.
However, the pull-ups may be pulling to 5V. What are the consequences of pulling the I2C pins higher than the Vdd?
The ADuM225x is a very old part and the understanding of safety limiting values has evolved over the years.
The safety limiting values are all about temperature rise in the device. Our isolators…