Limiting-Port Copper SFP+ Cables Use Low-Loss Dielectric

By leveraging both the Eye- Opener+ conductor technology and a low-loss expanded polytetrafluoroethylene (PTFE) cable dielectric, a series of "limiting-port" SFP+ cables fully complies with the SFF-8431 Revision 4.1, Chapter 3 specification for limiting modules. This product satisfies the limiting-port specification to 7 m without using active technology. SFP+ limiting ports are not required to provide electrical dispersion compensation (EDC) on the receive side. In addition, eliminating this chip or function has been projected to save $15 per port. Yet the loss of this function severely limits the distance over which traditional passive copper solutions can interoperate to less than 1 m. To satisfy the standard, integrators have been required to purchase active copper or optical transceivers. The specification-compliant 7 m is a length that spans a significant portion of the total interconnect space required for typical high-performance computing environments. The core/skin design of the cables provides a distributed or "per-unit-length" equalization without resistor-inductor-capacitor (RIC) circuitry required on the connector paddle card. Finally, the equalized cables vow to reduce jitter because the transfer function (frequency response) of the cable is "flattened" in the appropriate frequency band.

W.L. Gore & Associates, Inc., 385 Starr Rd., Landenberg, PA 19350-9221; (800) 311-3060, FAX: (800) 757-4673, Internet: www.gore.com.

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