The LP2950 and LP2951 are micropower voltage regulators with very low dropout voltage (typically 40mV at light loads and 380mV at 100mA), and very low quiescent current (75μA typical). The quiescent current of the LP2950/LP2951 increases only slightly in dropout, thus prolonging battery life.

Additional Features:
High accuracy 5V, guaranteed 100 mA output
Extremely low quiescent current
Low-dropout voltage
Extremely tight load and line regulation
Very low temperature coefficient
Use as regulator or reference
Needs only 1μF for stability
Current and thermal limiting
LP2951 Versions Only
Error flag warns of output dropout
Logic-controlled electronic shutdown
Output programmable from 1.24V to 29V

LDO (Low Dropout) Linear Voltage Regulators, Microchip