I note there appears to be no statement in the datasheet for the ADG5412 stating what the switch resistance is when the part is not powered. Some parts do explicitly state that this is high resistance when the part is not powered, does anyone know the swithch resistance of the ADG5412 when the part is not powered? Thanks.
There is no specification for resistance when the part is unpowered because applying a signal while the switch is unpowered is operating it above the absolute maximum ratings and is likely to damage it.
The signal should not go above the supply voltage, even when the part is unpowered.
If you need a device that can handle a signal without power, the ADG4612 has power-off protection.