Fixed 15 V rail at 1 A — headroom and dropout
The LM2940IMP-15/NOPB delivers a fixed 15 V output at up to 1 A continuous, with a maximum dropout voltage of 1 V at that full load. That means the input rail must stay above 16 V to keep the output in regulation; budget 16.5 V minimum for margin across temperature and line transients. Output configuration is positive and fixed — no external resistor divider needed, which saves two resistors and a feedback node on the board.
Protection set and quiescent current
On-chip protection covers over current, over temperature, reverse polarity, and short circuit — the regulator survives a hard output short or a reversed input battery without external clamp diodes. Quiescent current is 10 mA typical, with a supply current maximum of 15 mA. That Iq is higher than a modern CMOS LDO, but the LM2940 series was designed for low-dropout bipolar performance; the trade-off is a few milliamps of standing current for 1 A output capability and robust fault tolerance.
Package and temperature grade — SOT-223 layout
Not AEC-Q100 qualified, so not a direct fit for under-hood automotive, but fine for cabin electronics or auxiliary power in a non-critical path.