>I am constructing a battery operated PIC application where I need to be
>able to handle 2 Lithium cells.  Since this produces up to 7.4V, this
>needs to be regulated down to 5V.  To maximise battery life, the
>regulator needs low dropout (100mV) and quiescent current in the low
>microamps range.  It should be able to supply up to 100mA peak.

Why not try a National Semis regualtor part # LP-2950.  It uses about 75 uA
quiescent and has a dropout that ranges from 40 mV to 450 mV (100 mA) and is
a fairly nice reference (4.94 - 5.06 Vdc).  It is the part that I am using
on all my new designs.

Dwayne