2.7V fixed LDO with 85dB PSRR at low frequencies
The LP5900SDX-2.7/NOPB is a single-output, positive fixed LDO regulator from Texas Instruments, delivering 150 mA at 2.7 V with a maximum dropout of 0.15 V at full load. Power-supply rejection ratio spans 85 dB at 100 Hz down to 40 dB at 100 kHz — the low-frequency attenuation is strong enough to clean up ripple from a switching pre-regulator, but above 10 kHz the PSRR drops off and external filtering may be needed.
Package and board-fit for hand rework
Housed in a 6-WDFN exposed-pad package (6-WSON, 2.2x2.5 mm), the LP5900SDX-2.7/NOPB is surface-mount only. The enable pin lets you shut down the output; quiescent current drops to near zero when pulled low. Protection includes over-temperature shutdown and short-circuit current limiting — the part folds back, not latches, so a transient short on the output won't require a power cycle.
Active production and compliance
Input voltage max is 5.5 V — the part is designed for low-voltage rails, not automotive load-dump survival.