15V fixed LDO for industrial rails
The LM2937ES-15: It is designed for industrial and automotive-adjacent systems that need a clean, regulated 15V rail from an unregulated or higher-voltage supply — think motor-drive bias supplies, relay coil drivers, or sensor front-end power in factory automation.
Dropout and quiescent — the real-world margins
Budget at least 2V headroom between the input rail and the 15V output to stay in regulation across temperature and load. Quiescent current is 2 mA typical, rising to 20 mA max under supply current — this matters for always-on or battery-backed rails where the Iq eats into standby budget.
Package and thermal — D²Pak layout notes
Without that copper area, the 500mA output at high input-output differential will push the junction above 125°C quickly. The three-lead D²Pak footprint is shared with many TO-263 fixed regulators, but the pinout (input, ground, output, tab = output) is standard for this family.
Protection features — built-in ruggedness
Over-temperature shutdown, reverse polarity protection, and short-circuit current limiting are integrated — no external clamp diodes or crowbar circuits needed for basic fault tolerance. In a 24V industrial supply environment where reverse-battery events happen during harness swaps, the reverse polarity protection saves a board spin.
NRND status — plan the BOM transition
This means Texas Instruments will continue to manufacture it for existing production orders but does not recommend it for new designs. For new BOMs, evaluate pin-compatible 15V fixed LDOs in TO-263 from other vendors; for existing production, secure last-time-buy quantities or transition to a qualified alternate during the next board revision.