33 µH, 280 mA, 948 mOhm — the fit check for a power rail
The Murata LQH3NPN330MJRL is a 33 µH shielded wirewound inductor in the LQH3 series, built for surface-mount DC-DC converter output filters and power-line smoothing where the 280 mA continuous current rating and 948 mOhm max DCR define the thermal budget.
The ferrite core is fully shielded, which keeps the magnetic field contained — relevant when the inductor sits next to a sensitive ADC or RF section on the same board. The 420 mA saturation current is 50 % above the rated DC current, so the inductance holds up under transient peaks without crashing into a hard roll-off. Self-resonant frequency is 15 MHz, which means the inductor behaves as an inductor well below that point — for a 1–2 MHz switching regulator the impedance stays inductive, not capacitive. The 1 MHz test frequency is the standard for this inductance value.
1212 footprint and rework reality
It is a standard two-terminal ferrite drum core — no hidden thermal pad, no orientation ambiguity. The part is symmetric, so pin 1 is not a concern; the solder joint is on the end caps, visible and inspectable after reflow. Operating temperature range is -40 °C to 105 °C, which covers industrial ambient but not the full automotive under-hood band. The ferrite core material handles the temperature without significant inductance drift; the DCR will rise with temperature per the copper wire's positive TCR.