65V input LDO for harsh-environment rails
The Maxim MAX5023LASA+ is a 5V fixed-output positive linear regulator rated for 150mA output current and a 65V maximum input, making it a fit for automotive, industrial, and telecom systems where the supply rail can see transients well above 12V or 24V. The 1.5V dropout at full load means you need at least 6.5V on the input to hold regulation — typical for high-voltage LDOs with this headroom. Quiescent current sits at 140 µA, which keeps the always-on or standby draw manageable in battery-backed designs.
PSRR and protection set
Power-supply rejection ratio is 54 dB at 100 Hz — enough to clean up line-frequency ripple from a rectified AC source or a switching pre-regulator for sensitive analog loads. The part packs Enable, Hold, Reset, and Watchdog control features, plus over-temperature, reverse-polarity, and short-circuit protection. That watchdog is unusual for a simple LDO and suggests it was designed for safety-critical or supervised-rail applications where a missing clock triggers a reset.
Housed in an 8-SOIC (0.154", 3.90mm width) — surface-mount, standard footprint, easy to hand-rework with hot air or a soldering iron. MSL level is not in the record, but an 8-SOIC typically runs MSL 1 or 2; if the bag seal is broken, a short bake before reflow is cheap insurance. The 150mA output means the package handles the dissipation without a thermal pad — just normal copper pour on the PCB.