470 Ohm bead for a 950 mA rail
The Murata BLM15EX471SN1D is a single-line ferrite bead from the EMIFIL® BLM15 series, offering 470 Ohms impedance at 100 MHz while carrying up to 950 mA continuous current. In a 3.3 V digital rail, that 280 mOhm maximum DCR drops about 266 mV at full rated current — the voltage budget at the load needs that headroom above the regulator setpoint.
Where the temperature range matters
The ferrite material's impedance curve shifts with temperature — at 125°C the peak impedance frequency drifts lower, but the 470 Ohm spec at 100 MHz is the reference point for room-temperature design. For a power supply output filtering a switching regulator running at 1-2 MHz, the bead's impedance at that frequency (typically lower than the 100 MHz figure) is the relevant number for attenuation.
Active production, sourced to order
Listed as Active by Murata.