56 µH at 200 mA — the DC bias and loss trade-off
The LQH43NN560K03L is a Murata drum core wirewound inductor from the LQH43 series, rated 56 µH at 1 MHz test frequency with ±10% tolerance. The 200 mA current rating sets the DC bias limit — above that the inductance starts rolling off as the core approaches saturation. With a maximum DCR of 1.7 Ohm, the resistive loss at full rated current is about 68 mW — negligible for most power rail filters, but worth checking if the inductor sits in a high-ambient spot on the board. The self-resonant frequency of 9.3 MHz tells you where the impedance peak lives — above that frequency the part looks capacitive, so keep the switching or ripple frequency well below that for a clean inductive response.
1812 footprint and unshielded construction
The unshielded construction means the magnetic field extends outside the core, so keep it away from sensitive traces or other magnetics that could couple noise. Ferrite core material gives stable inductance over frequency up to the SRF, with a Q factor of 35 at 1 MHz — typical for a general-purpose wirewound choke in this size class. Operating temperature range spans -40°C to 105°C, covering most industrial and automotive cabin environments without derating concerns.