1.2 µH unshielded drum core for RF bias and filtering
The Murata LQH31MN1R2K03L is a 1.2 µH unshielded wirewound inductor in the LQH31 series, built on a ferrite drum core. The wirewound construction delivers a Q of 35 at 10 MHz, with a self-resonant frequency of 90 MHz — the useful band for impedance matching and bias-T applications sits well below SRF, where the component behaves inductively. The 900 mOhm DCR means a 24.5 mV drop at full rated current — budget this into the supply rail if the inductor sits in a power path.
1206 footprint and unshielded layout constraints
The unshielded construction radiates magnetic flux — adjacent traces carrying sensitive analog signals or high-impedance nodes should maintain at least one body width (3.2 mm) of clearance to avoid coupled noise. The ±10% tolerance on the 1.2 µH nominal value is typical for drum-core wirewound inductors; for resonant circuits or filters where inductance accuracy matters, measure the actual value at the operating frequency and temperature.