Würth is offering a surface-mount quad transformer for 1000Base-T Ethernet LAN connections. “WE-LAN AQ transformer convinces in an exemplary fashion in terms of crosstalk, insertion loss, return loss, differential and common-mode rejection,” claimed the firm, without giving figures. Inside, there are transformers and (smaller) common-mode chokes However, this data sheet gives the numbers as: crosstalk (1-100MHz) ...

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