3.3 µH Shielded Power Inductor for Automotive and Industrial DC-DC
The Coilcraft LPS4018-332MRC is a 3.3 µH shielded drum core inductor rated for 1.4 A continuous DC current with a saturation current floor of 1.9 A. The 80 mOhm maximum DCR sets the I²R loss budget for the power stage — at full rated current the self-heating is roughly 157 mW, which the 1.80 mm seated height must dissipate into the board copper. That certification is the gate for any under-hood or cabin-electronics BOM that must survive 125°C ambient.
Parametric Fit for Buck Regulator Output Filtering
The 3.3 µH value at 100 kHz test frequency is a common choice for 1-2 MHz switching regulators stepping 5 V or 12 V rails down to 1.8-3.3 V at 1-2 A loads. The 75 MHz self-resonant frequency sits well above any practical switching frequency, so the inductor behaves as a pure inductance in the regulator's passband. Shielded construction contains the magnetic flux within the ferrite core — adjacent power-stage components or a nearby RF section see minimal stray field coupling. In a dense 4-layer automotive ECU layout, this avoids the cross-regulation and noise injection that unshielded drums cause. The 1.9 A saturation current is the hard limit where inductance drops by 30% — the regulator's peak inductor current during load transients must stay below this value to maintain output ripple control. The 1.4 A continuous rating leaves 36% headroom for transient peaks, which is adequate for most point-of-load converters.
Active Lifecycle and Sourcing Posture
Sourced through independent distribution channels. Current pricing and lead time are confirmed at RFQ against the buyer's BOM quantity. No stock-holding claim is made; availability is verified per inquiry.