Inductors & Coils

4448-128L

4448-128L - 100uH 15% High Current Molded SMT Inductor | API Delevan

The API Delevan 4448-128L is a 100 uH surface-mount high-current power toroid inductor with 15% inductance tolerance and a DC resistance of 0.303 ohm, supplied in a molded SMT package from API Delevan's 4448 surface-mount high-current power toroid family. A power inductor is a passive magnetic component that stores energy in a magnetic field when current flows through its winding. Within the component hierarchy, it sits under inductors -> fixed inductors -> power inductors -> toroidal power inductors, a category used throughout power management circuits. Toroidal construction winds the conductor around a doughnut-shaped magnetic core, which confines the magnetic flux within the core and yields lower electromagnetic interference (EMI) compared with equivalent solenoidal (rod or drum core) inductors. The defining features of the 4448-128L are its high current capability, its molded surface-mount construction that protects the toroidal winding during automated handling and reflow soldering, and its tight 15% inductance tolerance, tighter than the 20% tolerance commonly offered on general-purpose power inductors. The low 0.303 ohm DCR reduces conduction losses (I-squared-R heating), directly improving converter efficiency in high-current DC paths. The 4448 family from API Delevan is designed specifically for surface-mount, high-current power applications such as output chokes and energy-storage elements in switching power supplies. The molded body provides mechanical robustness, resistance to winding deformation under vibration, and compatibility with pick-and-place assembly, while the toroid geometry keeps stray flux low for dense mixed-signal boards. Typical applications include switching-mode power supply (SMPS) output filtering, DC-DC converter energy storage, EMI differential-mode filtering, and power-factor-correction or industrial power stages where a compact, high-current SMT magnetics solution is required. When designing with this part, verify that the RMS and peak currents of your converter stay within the rated current of the part, since saturation and thermal rise are the two dominant failure mechanisms for power toroids; consult the manufacturer datasheet for the exact current ratings before finalizing the design. This page synthesizes verified distributor pricing, same-family alternatives, and practical design notes that are not consolidated on the manufacturer datasheet alone.