560 µH drum-core wirewound for filtering and energy storage
The Murata LQH43NN561K03L is a 560 µH drum-core wirewound inductor from the LQH43 series, designed for surface-mount assembly in power supply filtering, DC-DC converter output chokes, and general-purpose energy storage applications. Rated at 70 mA continuous current with a maximum DC resistance of 14.5 Ohm, the I²R loss at full load reaches roughly 71 mW — within the thermal budget of the 1812 package in still air. The unshielded construction means the magnetic field radiates; keep sensitive traces or low-impedance loops at least one part width away in layout.
Self-resonant frequency and Q factor define the usable band
With a self-resonant frequency of 2.7 MHz, the inductor behaves inductively from DC up to roughly one decade below that point; above ~2 MHz the impedance becomes capacitive and the part loses its filtering function. A Q factor of 40 at 796 kHz means the inductor stores 40 times more energy than it dissipates per cycle at that frequency — adequate for resonant tank circuits or EMI filters in the 100 kHz to 1 MHz range.