22 µH, 220 mA — the thermal budget tells the story
The LQH32NH220J23L is a Murata LQH32 series wirewound drum core inductor, 22 µH ±5% tolerance, rated for 220 mA continuous current. The 888 mΩ max DC resistance is the number that governs the real-world temperature rise: at 220 mA, I²R loss is roughly 43 mW, which in the 1210 (3225 metric) body stays under a 40°C self-heating rise in still air at 85°C ambient.
AEC-Q200 qualification means this inductor passed the full automotive stress suite: thermal shock, moisture resistance, mechanical shock, and vibration per the passive-component qualification standard.
Q factor and self-resonant frequency — filter and DC-DC fit
Q is 35 minimum at 1 MHz, and the self-resonant frequency is 20 MHz. For a buck converter switching at 1–2 MHz, the inductor's impedance stays inductive well above the switching harmonic content — the SRF is an order of magnitude above the fundamental, so parasitic capacitive coupling through the winding is negligible in the passband. Unshielded construction means the external magnetic field is not contained by a ferrite shield — adjacent traces carrying sensitive analog signals or high-impedance nodes should be kept at least one body width (3.2 mm) away to avoid coupling. The ferrite core material is standard MnZn, which saturates around 0.4–0.5 T; the 220 mA rating keeps the flux density well below saturation onset.