22 µH wirewound in a 1812 footprint
The Murata LQH43MN220J03L is a 22 µH unshielded wirewound inductor in the 1812 (4532 Metric) surface-mount package, part of the LQH43 series. It is rated for 320 mA continuous current with a maximum DC resistance of 940 mOhm.
Parametric fit for DC-DC and filtering
The 22 µH inductance is tested at 1 MHz, with a self-resonant frequency of 15 MHz — the inductor behaves as an inductor up to that point, after which parasitic capacitance dominates. The Q factor of 35 at 1 MHz indicates moderate ac losses; for a boost or buck converter switching near 500 kHz, the 15 MHz SRF provides ample margin above the switching harmonic content. Unshielded construction means the magnetic field extends beyond the core — keep sensitive traces or other magnetics at least one part-width away to avoid coupling. The ferrite core material suits frequencies from tens of kHz to a few MHz.