Noise floor and stability for precision analog chains
The LM4121AIM5-ADJ/NOPB: The series topology means the output doesn't need an external resistor divider for the basic voltage — the adjustable pin sets the output via two external resistors, and the 1.216 V minimum output is the internal bandgap voltage.
SOT-23-5 footprint — board-level reality
Housed in a standard SOT-23-5 (SC-74A) package, the part is a drop-in for the common 5-pin SOT-23 footprint with 0.95 mm pitch. For rework, standard hot-air profiles for SOT-23-5 work fine; the exposed die attach pad is on the bottom, so a preheat to 150°C avoids thermal shock during removal.