12 µH wirewound inductor for power and signal filtering
The Murata LQH43MN120J03L is a drum core, wirewound inductor in the LQH43 series, offering 12 µH inductance with ±5% tolerance in a standard 1812 (4532 Metric) surface-mount package. Rated for 380 mA continuous current with a maximum DC resistance of 620 mOhm, this part suits low-to-moderate current rails in DC-DC converters, EMI filtering, and signal conditioning where the unshielded construction is acceptable.
Key electrical parameters and what they mean for your circuit
The 12 µH inductance at 1 MHz test frequency, combined with a self-resonant frequency of 21 MHz, means the inductor behaves as an inductor up to roughly 21 MHz — above that, parasitic capacitance dominates and the impedance rolls off. A Q factor of 35 at 1 MHz indicates moderate efficiency at that frequency; for higher-Q needs in tuned circuits, a different core geometry may be preferred. The 620 mOhm DCR produces about 90 mW of I²R loss at full rated current — a factor to budget in thermal design, especially in dense boards with limited airflow.
The unshielded drum core design means magnetic flux radiates from the component — keep sensitive traces or low-impedance loops at least 2–3 mm away to avoid coupling.