Quote:Remove R1 and R2, take Out node to '-' input of opamp, then you just have a regular unity-gain buffer.
If you take the OUT Node shown in Fig. back to Opamp I/p Terminal, then it is not a Unity Gain Config.
Unity Gain Config will only be formed when you take the Opamp Output( i.e. gate of pMOS ) directly to it's i/p which doesnt make any sense for LDO.
Taking OUT node back to opamp is Ok, & it's done sometimes.
Just take care of the Big Bypass Cap you put at OUT Node doesnt affect the I/p Terminal of the Opamp.
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Mayank