The datasheet recommends that VIN ≥ VOUT(nom) + 1 V. However, under normal operation in section 8.4.1 it lists one of the modes as: The input voltage is greater than the nominal output voltage added to the dropout voltage.
What is the reason for the 1V headroom and if that is necessary why is there even a drop out value listed that is less than 1V?
I want to use this part in an application where there is 11.5V Vin and 11V VOUT with 20mA current. I appears that would be ok based upon figure 9. Yes?