Last Buy — what it means for your BOM
Murata has marked the LQH31MN220J03L as Last Buy. For a replacement, the closest parametric match within the LQH31 family would need to be evaluated — same 22 µH inductance, ±5% tolerance, and 1206 footprint — but pin-compatibility is not guaranteed without a datasheet review.
22 µH, 85 mA — signal filtering fit
The LQH31MN220J03L is a 22 µH drum core wirewound inductor rated for 85 mA continuous current. The 4.03 Ω maximum DCR means the DC power loss at full rated current is about 29 mW — acceptable for low-power signal conditioning or decoupling in RF and analog circuits, but not for high-efficiency power conversion. Self-resonant frequency is 14 MHz, and Q is 40 at 2.5 MHz. This makes the part suitable for filtering in the low-MHz range — for example, as a choke in a 2.4 GHz BLE front-end it would be well below resonance, but the 14 MHz SRF limits its use above about 5 MHz where the impedance becomes capacitive. The ferrite core material provides stable inductance over this range, though the unshielded construction means the field radiates — keep sensitive traces or adjacent inductors at least a few mm away to avoid coupling.
1206 footprint — board integration
The tape-and-reel packaging supports automated pick-and-place; the cut-tape option is available for prototyping. The part is unshielded — the magnetic field extends beyond the body, so board layout should maintain clearance from other inductive components or sensitive analog traces. The wirewound construction gives a higher Q and lower DCR than a multilayer ferrite bead at this inductance, but the trade-off is larger physical size and radiated field.