RJ-45s Integrate Necessary Passives

The HyperJack shielded RJ-45 modular jacks feature integrated magnetics, capacitors and resistors, resulting in fewer components needing to be mounted on the printed circuit board. The magnetics, wire-wound components in the jacks, promise to reduce common-mode noise and enable dc insulation of the cable side, as opposed to the board side of the connection.
The capacitors and resistors terminate noise from the non-used cable pairs and are said to contribute to the electrical balance of the common-mode noise of the signal pairs. Integrated common-mode chokes also help to achieve a better signal-to-noise ratio.
Price for these IEEE 802.3-compliant modular jacks is $1.63 each/10,000 with a lead time of six to eight weeks.