NRND status and BOM planning
The ACM4520V-421-2P-T00: This means the part remains available for existing production BOMs, but TDK will not support new design-ins. A BOM engineer should evaluate a migration path or secure a last-time-buy quantity for the program's remaining build window. For a new design, a functionally equivalent part from the same ACM-V series — same 420 Ohms impedance at 100 MHz, same 1.4 A rating, same footprint — would be the natural starting point for a pin-compatible alternative. Confirm the exact order code with TDK's current product selector.
Automotive qualification and deployment envelope
Rated AEC-Q200, this filter meets the passive-component qualification standard for automotive electronics. The OEM auditor will expect PPAP documentation and a zero-defect lot trace; the AEC-Q200 stamp confirms the part passed thermal shock, vibration, and moisture resistance testing per the AEC component technical committee. The 50 V DC rating provides margin above the nominal rail voltage, including load-dump transients that can reach 40 V on a 12 V bus.
420 Ohms at 100 MHz targets conducted common-mode noise on the power input line — the typical frequency band for switching noise from a DC-DC converter or a motor-drive PWM stage. The impedance peak attenuates the noise before it propagates to the rest of the system. Rated 1.4 A continuous with a maximum DC resistance of 55 mOhm. At full current the I²R loss is 108 mW — well within the SMD package's thermal budget at 125°C ambient, but the derating curve should be checked if the ambient temperature exceeds 85°C or if airflow is restricted.
PCB footprint and mounting
The 4-pad layout is designed for reflow soldering; the two outer pads carry the line current, the inner pads are the common-mode return path. Surface-mount assembly with standard reflow profile. The tape-and-reel packaging (Cut Tape also available) supports automated pick-and-place for high-volume production.