3.3 µH drum-core inductor for DC-DC filtering and bias-T circuits
The Murata LQH43MN3R3M03L is a 3.3 µH ±20% drum-core wirewound inductor in the LQH43 series, built on a ferrite core and housed in an unshielded 1812 (4532 Metric) surface-mount package. Rated for 500 mA continuous current with a maximum DC resistance of 350 mOhm, the part suits power-supply filtering and signal-path decoupling where the DC bias stays below the current ceiling to avoid saturation. The self-resonant frequency of 47 MHz means the inductor behaves inductively well into the HF band, making it usable in low-frequency switching regulators and RF bias networks up to tens of megahertz.
Unshielded construction and board layout considerations
Because the part is unshielded, the magnetic field radiates from the drum core — keep the inductor away from sensitive analog traces, high-impedance nodes, and adjacent magnetics to avoid coupling. Inductance is tested at 1 MHz, and the Q factor is 20 at that frequency — a moderate Q that indicates acceptable AC loss for general-purpose filtering.