IEEE 1394

IEEE 1394 Interface

Type	Serial
Production history
Designer	Apple (1394a/b), IEEE P1394 Working Group, Sony, Panasonic, etc.
Designed	1986; 38 years ago (1986)[1]
Standardized	January 1995; 29 years ago (1995-01)
Manufacturer	Various
Produced	1994–current
Superseded by	Thunderbolt (and USB 3.0 for consumer use)
General specifications
Length	4.5 meters maximum
Width	1
Hot pluggable	Yes
Daisy chain	Yes, up to 63 devices
Audio signal	No
Video signal	No
Pins	4, 6, 9
Electrical
Max. voltage	30 V
Max. current	1.5 A
Data
Data signal	Yes
Bitrate	1394a, half-duplex 100–400 Mbit/s (12.5–50 MB/s) 1394b and later, full-duplex 800–3200 Mbit/s (100–400 MB/s)

IEEE 1394 is an interface standard for a serial bus for high-speed communications and isochronous real-time data transfer. It was developed in the late 1980s and early 1990s by Apple in cooperation with a number of companies, primarily Sony and Panasonic. It is most commonly known by the name FireWire (Apple), though other brand names exist such as i.LINK (Sony), and Lynx (Texas Instruments).

The copper cable used in its most common implementation can be up to 4.5 metres (15 ft) long. Power and data is carried over this cable, allowing devices with moderate power requirements to operate without a separate power supply. FireWire is also available in Cat 5 and optical fiber versions.

The 1394 interface is comparable to USB. USB was developed subsequently and gained much greater market share. USB requires a host controller whereas IEEE 1394 is cooperatively managed by the connected devices.^[2]