[FAQ] TMUX1308-Q1: Fail-safe operation

Hello Sreenivasa,

The linked thread you provided discusses about the signal on the address pins of the device. 

You mentioned applying an input voltage when the supply is not available.

Do you mean a signal going into the address pins or the source pins? If it is the address pins, then there is no issue because of the fail safe logic feature, but if the input is to the source and drain pins (I/O) its a different story. You will need a current limiting resistor on the input for it to work. 

Thanks,

Nir 

Hello Sreenivasa,

Understood, no the source pins won't cause any back feed on the supply pin due to the injection current control feature the device has.

More information on the injection current control feature can be found in the datasheet

Thanks,

Nir