What the 47 µH rating means for a DC-DC filter
The LQH43PB470M26L is a 47 µH shielded wirewound inductor from Murata's LQH43 series, built on a ferrite drum core and wound for surface-mount assembly in the 1812 (4532 Metric) footprint. Rated at 280 mA continuous current with a DC resistance of 861.3 mOhm max, the part's copper loss at full load is I²R ≈ 67.5 mW — well within the self-heating budget for a 125 °C ambient ceiling. The 470 mA saturation current (Isat) provides headroom above the continuous rating, meaning the inductance holds within tolerance under transient peaks typical of a buck converter's inductor ripple current.
Shielding and self-resonant frequency — where it fits
The ferrite core is shielded, which reduces radiated EMI coupling into adjacent traces or nearby low-noise analog circuitry — a consideration when the inductor sits close to a sensor front-end or RF section on the same board. Self-resonant frequency is 8 MHz; above that the component behaves capacitively and loses inductive impedance. For a switching regulator switching at 500 kHz to 2 MHz, the 47 µH value keeps the impedance inductive across the fundamental and first few harmonics. Inductance is tested at 1 MHz, which is the standard measurement frequency for this value range — the core material's permeability is stable from DC up to several MHz before roll-off begins.
The LQH43PB470M26L is supplied in tape-and-reel packaging (TR), compatible with standard pick-and-place equipment for the 1812 footprint.