BBB Ethernet PHY Isolation


regarding the LAN8710A [0] Ethernet transceiver used on the BBB, I'd
like to know whether it is isolated or not?

According to the datasheet [0, Page 41] , it has an "Isolate Mode" hat
is /disabled/ by default.

In my application I use a normal pin header instead of RJ45, so in
principle a user could short-circuit them or apply extraordinary high or
reverse voltages...
Is it therefore safe to use the BBB as is, or would I need to add an
isolator or optocoupler?
If used as is, what could possibly be damaged? If just the PHY blows up,
it would be fine. A short-circuit of the voltage regulators, or a reset
of the processor and the like I consider as "bad".



The transformer performs the isolation function. So if you are not using that, you will need to add your own based on whatever your needs are.

Whether it is “safe” to use it as is or not, as long as you are using it as an Ethernet cable connection, which is what it was designed to do, it is safe. Anything outside of that, you will need to decide what is needed to make it safe.