39 µH wirewound in a 1812 footprint
The Murata LQH43NN390J03L is a 39 µH unshielded drum-core wirewound inductor in the LQH43 series, housed in a standard 1812 (4532 Metric) SMT package. The ferrite core and wirewound construction give it a Q factor of 35 at 1 MHz, which means the inductive reactance dominates the AC losses at that test point — useful for tuned circuits or filtering where the Q sets the selectivity or ripple attenuation. The self-resonant frequency of 11 MHz marks the upper bound where the inductor stops behaving inductively — above that, parasitic capacitance dominates and the impedance rolls off.
Board-fit and footprint
Surface-mount reflow compatible — the ferrite core handles standard lead-free profiles without cracking, but the unshielded construction means the magnetic field couples into adjacent traces or components within a few mm of the body. Keep power-stage inductors at least one part-width from sensitive analog or RF traces.