FireWire® Connectors Information
IEEE 1394 connectors are used to connect FireWire® devices such as host controllers, adapters, hard drives, hubs, repeaters, and card readers. FireWire, a registered trademark of Apple Computer, is a communications protocol for the transmission of data, video, and audio over a single cable at very high bit rates. IEEE 1394 is an interface standard adopted by the Institute of Electrical and Electronics Engineers (IEEE) for digital data transfers at 400 Mbps. The popularity of IEEE 1394 is due in part to its use of a bus-powered architecture that does not require peripherals to supply their own power. Products that support the IEEE 1394 standard adhere to its specifications, but often use proprietary trade names. For example, Sony uses the term iLink® to describe its FireWire products. iLink is a registered trademark of the Sony Corporation.
There are two basic types of IEEE 1394 connectors: four-pin and six-pin. Four-pin or four-position FireWire connectors are used with digital video camcorders and other devices that have a small footprint and do not require external power. By contrast, six-pin or six-position connectors are used with personal computers (PCs), rewritable compact disc rewritable drives (CDRWs), external hard drives, digital audio stations, and other larger, more durable FireWire devices that use external power. Four-pin connectors are rectangular, 1/4” by 1/8” devices in which one of the longer sides is indented. Six-pin connectors are rectangular, 1/2” by 3/16” devices in which one of the smaller sides is rounded. Four-pin and six-pin IEEE 1394 connectors are either straight or right-angled.
Performance specifications for IEEE 1394 connectors include voltage rating, current rating, insulation resistance, electrical resistance and operating temperature. Voltage rating and current rating are maximum values. Insulation resistance is the electrical resistance between two conductors that are separated by an insulating material. Contact resistance is the electrical resistance of mated contacts when assembled in a connector under typical service. Typically, electrical resistance is determined by measuring from the rear of the one contact to the rear of its mate, excluding both crimps, while carrying a specified test current. Overall contact resistance is a wire-to-wire measurement.
IEEE 1394 connectors are used in a variety of computer-controlled home entertainment, communication, and appliance networks. In audio-visual (A/V) applications, they are used mostly in digital camcorder outputs. Microsoft’s implementation of multiple IEEE 1394 ports with versions of Microsoft® Windows® XP® promises to expand the use of IEEE 1394 connectors in multimedia connections. Microsoft, Windows and Windows XP are registered trademarks of Microsoft Corporation.