150 µH Shielded Inductor for Automotive Power Rails
The Coilcraft LPS4018-154MRC is a 150 µH shielded drum core inductor from the LPS4018 series, qualified to AEC-Q200 for automotive applications. It delivers 280 mA continuous rated current with a saturation current of 270 mA, making it a fit for DC-DC converter output filters and EMI suppression in power management circuits where the load stays under that ceiling. The 2 Ohm maximum DCR at 150 µH sets a conduction loss floor — at 280 mA the I²R loss is 157 mW, which the 3.90 mm x 3.90 mm package must dissipate without exceeding the 125°C rated operating temperature.
AEC-Q200 Qualification and Operating Range
Rated AEC-Q200, the LPS4018-154MRC carries the automotive passive-component stress qualification (temperature cycling, moisture resistance, mechanical shock, and solder heat) that Tier-1 and OEM PPAP auditors require.
Self-Resonant Frequency and Current Saturation Margin
The self-resonant frequency is 8 MHz — above this point the inductor behaves capacitively, so the switching converter's fundamental ripple frequency must stay well below 8 MHz for the inductance value to hold. A 400 kHz to 2.2 MHz switching regulator is within the usable band; a 4 MHz+ converter would push the impedance past resonance. Saturation current is 270 mA, just 10 mA below the 280 mA continuous rating. This narrow margin means the inductor's core begins to lose inductance before the thermal rating is reached — a transient overload above 270 mA causes a hard inductance drop, not a gradual roll-off. Design the peak current budget with at least 20% headroom below 270 mA to stay in the linear inductance region.
The footprint is a 3.90 mm square pad layout — confirm the land pattern matches the Coilcraft recommended PCB layout for the LPS4018 series, as the nonstandard designation means no generic JEDEC outline applies. The shielded construction contains the magnetic field within the ferrite core, reducing radiated EMI to adjacent traces or components on a dense automotive PCB.