120 Ohm ferrite bead in 0402 for supply-line filtering
The BLM15EG121SN1D is a single-line ferrite bead from Murata's EMIFIL® BLM15 series, offering 120 Ohms impedance at 100 MHz — the frequency where conducted EMI from switching regulators and digital ICs typically peaks. Rated for 1.5 A continuous current with a maximum DC resistance of 95 mOhm, the voltage drop at full load is under 143 mV — negligible for most logic rails but worth checking if the downstream device has a tight tolerance supply. The 95 mOhm DCR also sets the self-heating: at 1.5 A, dissipation is about 214 mW, well within the 0402 body's capability in still air.
NRND lifecycle — plan the BOM transition
Murata has designated the BLM15EG121SN1D as Not Recommended for New Design (NRND). This means it remains available for existing production but is not intended for new board spins. No pin-compatible alternative is listed by Murata, so a BOM change for new designs will require a parametric search for a 120 Ohm 0402 ferrite bead with at least 1.5 A rating.