2.5V fixed rail for harsh environments
The Texas Instruments LM2937ESX-2.5/NOPB is a positive fixed LDO regulator delivering a 2.5V output at up to 500mA, with a maximum input voltage of 26V. The DDPAK/TO-263-3 surface-mount package (the same footprint as D²Pak) gives good thermal transfer through the tab to the board copper, which matters when you're pulling near the 500mA limit at high ambient.
Protection and dropout — what the ratings mean
On-chip protection covers over-temperature, reverse polarity, and short circuit — three failure modes that kill unguarded regulators in field returns. The reverse polarity protection is especially useful in battery-powered or vehicle applications where the input can get swapped. Maximum dropout is 1V at 50mA load, so with a 3.5V input rail you still hold regulation at light loads. At full 500mA output, expect dropout to rise — the datasheet curve shows it, but the 1V figure at 50mA gives you the low-load margin. Quiescent current is 2 mA typical, which is modest for a 500mA LDO — not the lowest-Iq part for battery-idle designs, but fine for always-on industrial rails where the load current dominates the budget.