There are three ways to actually do the delay’s, first is an RC delay from DVDD to the enable pin. However one should be careful about driving the enable pin with a logic signal that may be above that 1.8V rail, as to not back feed a higher voltage into the DVDD. The second alternative would be to feed in a higher voltage and use a delay off of VCCA. The third way is an RC delay from the input voltage to the enable pin. As long as the input voltage comes up in a standard way all the time, this is a good option, and allows any voltage to be applied to the enable signal within its allowed range.