3.3 µH shielded wirewound — parametric fit for DC-DC input/output filtering
The Murata LQH3NPN3R3MMRE is a 3.3 µH shielded wirewound inductor from the LQH3 series, built on a ferrite core in a 1212 (3030 Metric) surface-mount package. Its 1.55 A continuous current rating and 1.2 A saturation current (Isat) define the usable load range for a buck converter output filter or a module input choke — the saturation limit is the hard ceiling; once the core saturates, inductance collapses and ripple current rises sharply. DC resistance is 106 mOhm max, which at 1.55 A produces roughly 255 mW of I²R loss — within the thermal budget of the 1212 footprint for most board layouts, but worth checking against the ambient temperature derating if the inductor sits near a hot regulator or in a confined enclosure.
Obsolete — last-time-buy channel for existing BOM positions
Murata has marked the LQH3NPN3R3MMRE as Obsolete. No official successor order code is recorded in the lifecycle data. New designs should migrate to an active Murata LQH3-series variant with matching 3.3 µH inductance, 1212 footprint, and similar DCR/saturation profile; the base product number LQH3NPN allows parametric filtering against the active portfolio.
Self-resonant frequency and temperature grade
The self-resonant frequency (SRF) is 70 MHz. Below SRF the component behaves as an inductor; above it, parasitic capacitance dominates and the impedance becomes capacitive. For a 500 kHz to 2 MHz switching regulator, the 70 MHz SRF provides ample margin — the inductor's impedance stays inductive across the fundamental and the first several harmonics.