33 µH, 200 mA — where this fits on the BOM
The Murata LQH32DN330K53L is a 33 µH drum core wirewound inductor from the LQH32 series, rated for 200 mA continuous DC with a DCR of 1.43 Ohm max. The self-resonant frequency of 17 MHz means it behaves as an inductor up through the low-MHz range — above that, parasitic capacitance dominates and the impedance rolls off. Saturation current is specified at the same 200 mA as the rated current, so there is no additional headroom beyond the DC bias limit — the inductance starts to roll off right at the rated current. For a 33 µH part in a buck converter or EMI filter, budget the peak inductor current below 200 mA to stay in the linear region.
Unshielded construction — layout implications
Unshielded means the magnetic field radiates from the core — adjacent traces carrying sensitive analog signals or high-impedance nodes need keep-out distance or a ground plane between them and this inductor. In a dense mixed-signal board, a shielded part may be preferable, but the LQH32DN330K53L costs less and fits where radiated coupling is manageable. Reflow soldering profile follows the standard lead-free ramp; the ferrite core and wirewound construction tolerate normal reflow thermal shock without cracking.
Active production, no obsolescence risk
Product status is Active — Murata continues to manufacture this part with no announced end-of-life or last-time-buy. The LQH32 series is a long-running product family, so supply continuity is stable through authorized distribution. The ferrite core material maintains inductance stability across the full temperature band within the ±10% tolerance.