Active production — no end-of-life notice on file
TDK lists the ACM4520-142-2P-T000 as an Active product. No PCN or EOL notice has been issued, so this part remains a standard catalog line for both new designs and replacement BOM positions.
1.4 kOhms at 100 MHz — the attenuation target
The common-mode impedance is 1.4 kOhms at 100 MHz. That places the notch squarely on conducted EMI from switching power supplies or digital clock harmonics in the 30–300 MHz range — the band most likely to fail CISPR 22 / FCC Part 15 radiated limits. At lower frequencies the impedance drops off; this filter is not effective below about 10 MHz. Rated for 1.7 A continuous current on the line. Push beyond that and the ferrite core saturates, collapsing the impedance to near zero — the filter stops filtering.
Horizontal 4-pad SMD — board-fit constraints
The package is a horizontal-mount common-mode choke with four pads — two input, two output. The horizontal orientation means the winding axis is parallel to the PCB, which keeps the profile low but the footprint is wider than a vertical-mount equivalent. Rated for surface-mount reflow soldering. The 50 V DC voltage rating limits it to low-voltage power rails or signal lines — not for mains or 48 V telecom bus applications.