63 dB PSRR at 1 kHz — clean rail for analog front-ends
The LP2980AIM5X-4.5/NOPB is a fixed 4.5 V output LDO from Texas Instruments, delivering 50 mA with a 63 dB power-supply rejection ratio at 1 kHz. That PSRR figure puts it in the class of regulators suited for powering precision analog blocks — op-amp rails, ADC reference buffers, or sensor bias lines — where ripple on the supply directly degrades signal-to-noise ratio.
220 mV dropout and 95 µA quiescent — low headroom, low idle
Maximum dropout is 220 mV at the full 50 mA load, so the input can drop to 4.72 V before regulation is lost. That matters for battery-powered gear where the cell voltage sags under load, or for a post-switcher rail that needs a clean 4.5 V with only a few hundred millivolts of headroom. Quiescent current is 95 µA typical, keeping the idle draw low in always-on subsystems.
The SOT-23-5 package (SC-74A) keeps the footprint small, but the thermal resistance means the 50 mA output is the practical limit at the high end of the temperature range without airflow.
For BOM lines that still call out this exact order code, the only path is the independent surplus market.