33 µH wirewound choke for filtering and bias-T circuits
The Murata LQH31MN330J03L is a drum core wirewound inductor in the LQH31 series, offering 33 µH inductance with ±5% tolerance in a standard 1206 (3216 Metric) surface-mount package. Rated for 80 mA continuous current, this part suits low-power DC-DC converter output filtering, bias-T networks, and signal-line chokes where the DC resistance of 3.8 Ohm sets the I²R heating budget. The unshielded construction means the magnetic field extends beyond the component body — keep sensitive traces or adjacent inductors at least one package width away to avoid coupling.
Frequency response and Q factor
Self-resonant frequency is 12 MHz, above which the inductor behaves capacitively — this sets the upper usable frequency for filtering applications. Q factor measures 40 at 2.5 MHz, indicating moderate efficiency in tuned circuits at that frequency — acceptable for narrowband impedance matching but not for high-Q resonant tank designs. Inductance is tested at 1 MHz, the standard reference frequency for this value range.
Supplied on tape and reel with cut-tape option, compatible with standard pick-and-place for the 1206 package class.