470 µH drum core wirewound — what the ratings mean for the BOM
The LQH43NH471J03L is a 470 µH unshielded wirewound inductor from Murata's LQH43 series, built on a ferrite drum core and housed in an 1812 (4532 metric) surface-mount package. The 75 mA current rating is the continuous DC current at which the inductance drop stays within tolerance — push beyond it and the core saturates, and the inductance falls off sharply. The 9.36 Ohm maximum DCR sets the I²R conduction loss: at 75 mA the self-heating is about 53 mW, negligible in most circuits, but the DCR also adds a voltage drop that matters in low-voltage rails.
AEC-Q200 and the 125 °C ceiling
Rated AEC-Q200, this inductor is qualified for automotive-grade stress — thermal shock, vibration, and solder-heat resistance per the AEC-Q200 passive-component standard. The unshielded construction means the magnetic field radiates; keep sensitive traces or other magnetics at least one part-width away to avoid coupling.