68 µH at 180 mA — the filter spec ceiling
The LQH43MN680K03L: Rated 68 µH ±10 % at 1 MHz test frequency, with a DC current rating of 180 mA. Above that current the ferrite core begins to saturate and the effective inductance rolls off — the 180 mA figure is the saturation-limited ceiling, not a thermal limit. DC resistance is 1.9 Ω max; at full rated current the I²R loss is 61.6 mW, which sets the self-heating floor before core losses add. The Q factor of 35 at 1 MHz tells you the energy storage efficiency is moderate — expect noticeable core losses if the ripple current pushes the AC flux density above 50 mT. Self-resonant frequency is 8.4 MHz. Above this point the winding capacitance dominates and the part behaves capacitively — keep the operating frequency below 4 MHz to stay clear of the SRF knee.
Unshielded drum core — board integration note
The unshielded ferrite drum core radiates the magnetic field openly. On a dense PCB, keep a 2–3 mm keep-out zone around the part if there are sensitive analog traces, other inductors, or a nearby RF section — the stray field couples into adjacent loops. The land pattern matches the generic 1812 solder pad layout; no special thermal pad or via array is required. The ferrite Curie temperature is well above 85°C, but the wire insulation enamel sets the upper bound; do not exceed 85°C ambient plus self-heating.