3.9 µH wirewound for power and signal filtering
The Murata LQH43NH3R9J03L is a drum core wirewound inductor in the LQH43 series, rated 3.9 µH with ±5% tolerance. It carries a 650 mA current rating and a maximum DC resistance of 144 mOhm, making it a fit for DC-DC converter output filtering or power rail smoothing where the 650 mA ceiling matches the load current. The 41 MHz self-resonant frequency means it stays inductive well above the switching frequencies of most buck converters, so the impedance curve is predictable up to that point. The Q factor of 20 at 1 MHz is typical for a ferrite-core wirewound in this inductance range — useful for tuned circuits or impedance matching at lower frequencies.
AEC-Q200 qualification and temperature range
This inductor carries AEC-Q200 qualification, the automotive passive-component stress test standard. That means it has passed thermal shock, vibration, solderability, and moisture resistance testing per the AEC-Q200 rev D regime.
1812 footprint and unshielded construction
The unshielded drum core design means magnetic flux radiates outside the component — keep sensitive traces or other inductors at least one package width away to avoid coupling. The ferrite core material gives stable inductance over temperature compared to powdered-iron cores, though saturation current is not listed in this spec set. For a 650 mA-rated part, the saturation knee typically sits above the rated current, but the actual margin depends on the DC bias curve in the full datasheet.