15 V fixed rail, 1 A continuous — the field-fit check
The Texas Instruments LM2940CS-15/NOPB is a fixed 15 V positive-output LDO regulator rated for 1 A continuous output current. It comes in a TO-263-4 (D2PAK) surface-mount package with three leads plus the tab, and operates over 0°C to 125°C.
Dropout headroom and input compatibility
Maximum dropout is 0.8 V at the full 1 A load. That means a 15 V output needs at least 15.8 V at the input pin to stay in regulation. With a maximum input of 26 V, this part works cleanly from a 24 V bus — common in factory automation — but is not compatible with a 5 V input, because the dropout alone eats more than the available headroom. For battery-backed or always-on rails, that Iq is worth noting — it is not a micropower LDO, but it is reasonable for a 1 A fixed-output part.
Protection set and PSRR for noisy environments
Built-in protection covers over current, over temperature, reverse polarity, and short circuit. That saves external clamp diodes and foldback circuits on the board. The 64 dB PSRR at 120 Hz means the output rejects a good chunk of full-wave-rectified ripple — useful when this regulator follows a transformer-and-capacitor front end rather than a switcher.