No, the data channels are a separate chip set, so they can be run independently
of what is happening with the isoPower converter. On side 1 the data channels
will still draw quiescent current and drive data to side 2. On side 2, if
power is available from a source other than Viso, it will continue to operate
normally. If side 2 is powered by Viso, it will shut down when Viso is
disabled, but side 1 power must be switched separately if you need low power
from the data section. A pass transistor controlled from the Pdis signal
should be used to turn power off to Vdd1.