NDMB252100 is a multi-pair Ethernet transformer module designed for high-speed data transmission in 1, 2.5, 5, and 10 Gbit/s Ethernet applications. The module features a 1:1 turn ratio with ±3% tolerance and supports four differential pairs, each rated for 960 mA current capacity. Key electrical characteristics include insertion loss of -2.0 dB maximum across 1–400 MHz and -3.0 dB maximum at 400–500 MHz, return loss of -22 dB minimum at 1–100 MHz, and open-circuit inductance of 160 µH minimum at 100 kHz. The transformer provides excellent signal integrity with crosstalk isolation of -28 dB minimum at 1–100 MHz and common mode rejection ratio of -30 dB minimum at 1–40 MHz. With 1,500 VAC isolation rating and Type B key connector configuration, this module is ideal for industrial Ethernet, telecommunications, and data center interconnect applications requiring robust, high-performance signal transmission.