33 µH wirewound for DC-DC filtering and bias-T applications
The Murata LQH32CN330K53L is a 33 µH ±10% drum core wirewound inductor in the LQH32 series, rated for 200 mA continuous current with a maximum DC resistance of 1.43 Ohm. The ferrite core and wirewound construction give it a self-resonant frequency of 17 MHz, which sets the practical ceiling for filtering or energy storage in a switching converter — above that frequency the inductor behaves capacitively and the impedance rolls off. Unshielded construction means the magnetic field is not contained within a ferrite sleeve — adjacent traces or components within a couple of millimeters may couple noise into the inductor or pick up its field. On a dense board, keep a keep-out zone around the body or switch to a shielded variant if crosstalk becomes an issue.
Where the 200 mA rating and 1.43 Ohm DCR matter for the BOM
The 200 mA current rating is the DC bias current at which the inductance typically drops by 10% from the nominal 33 µH — above that the core begins to saturate and the inductance falls off. For a buck converter output filter, budget the peak inductor current (DC load plus ripple) to stay under 200 mA to maintain the target inductance. A 1.43 Ohm DCR at 200 mA gives an I²R conduction loss of about 57 mW — negligible in most circuits but enough to raise the internal temperature a few degrees above ambient. The 17 MHz self-resonant frequency means this inductor is usable up to roughly 5-10 MHz in a power filter before the parasitic capacitance between windings dominates. For a 1 MHz switching regulator, the impedance at the switching frequency is still inductive; at 10 MHz the inductor is near resonance and should be avoided.
Board-fit: 1210 footprint and surface-mount assembly
The nonstandard case designation means the pad layout follows the 1210 footprint — standard 1210 solder pads work, but verify the land pattern against the Murata recommended pad geometry for the LQH32 series to ensure the solder fillet wicks properly on the end terminations. Tape-and-reel packaging (7-inch or 13-inch reel depending on the order quantity) feeds into standard pick-and-place. The part is compatible with reflow soldering; the ferrite core does not absorb moisture, so no bake-out is required before reflow unless the tape has been exposed to high humidity for extended storage.
Active production — sourcing posture
No immediate allocation constraints reported for this Murata LQH32 series part.