when the ADIN1200 is powered off

Hi,

An ADIN1200 that is powered off can be safely connected to a remote device which is currently active, this will not cause damage to the ADIN1200 MDI_X pins.

Best Regards,

Mark

thank you for your answer.
I understand not to destroy it.
However, when the power is turned off, the communication signal from the opposing machine will exceed the maximum absolute rating, so it is not guaranteed？

Hi,

There is protection circuitry internal to the MDI pins which will protect them when standard ethernet traffic is sent into an unpowered device.

Best Regards,

Mark

thank you for your answer.
Does the protection circuit mean that it is a circuit that suppresses the maximum absolute rating (0.3V because the power is not on) or less? Or is it OK to exceed the maximum absolute rating for a short period of time?

Yes in that case the ABS MAX rating is 0.3V, which is the highest DC voltage that can be constantly applied to the pin. The protection circuitry will project the devices against transients greater than this value for a short period of time.

thank you for your answer.

To summarize,
The signal coming from other powered devices via cables and pulse transformer when the power is off will exceed the maximum absolute rating of 0.3V in this state.
However, there is a protection circuit that does not break even if the maximum absolute rating is exceeded for a short time, so it will not break for a short time.

According to the current data sheet description method, this usage is not broken, but it can be read as out of warranty（because　exceed　he maximum absolute rating).
 I request to change the description in the datasheet (for example, ●●mS may exceed the maximum absolute rating).

thank you for your answer.

To summarize,
The signal coming from other powered devices via cables and pulse transformer when the power is off will exceed the maximum absolute rating of 0.3V in this state.
However, there is a protection circuit that does not break even if the maximum absolute rating is exceeded for a short time, so it will not break for a short time.

According to the current data sheet description method, this usage is not broken, but it can be read as out of warranty（because　exceed　he maximum absolute rating).
 I request to change the description in the datasheet (for example, ●●mS may exceed the maximum absolute rating).