Micro ribbon connector

Not to be confused with D-subminiature connectors.

The micro ribbon or miniature ribbon connector is a common type of electrical connector for a variety of applications, such as in computer and telecommunications equipment having many contacts.

Micro ribbon 14-pin female on a Philips VG-8235 MSX2 home computer

Micro ribbon 24-pin female on a LeCroy oscilloscope

Micro ribbon 36-pin female on a circuit board

Mini-Centronics 36-pin male connector (top) with Micro ribbon 36-pin male Centronics connector (bottom)

Mini-Centronics 36-pin male connector (right) with Micro ribbon 36-pin male Centronics connector (left)

Micro ribbon 50-pin female used as SCSI-1 interfaces

The connector contains two parallel rows of contacts within a shielded case having a characteristic D-shape similar to that used in D-subminiature connectors. The contacts are not pins, but small flat bands of metal, called ribbon contacts. The connectors are manufactured in many capacities, including 14-, 24-, 36-, 50-, 64-, and 100-pin varieties. They may be mounted on boards, panels, or may terminate cables. Wires are attached by means of solder, crimping or insulation displacement. Female connectors have bail locks for a sturdy connection to the male connector. Screws may also be employed to secure connections.

This connector type is also known as telco, 25-pair, miniature delta ribbon, mini D ribbon, delta ribbon, MDR, Amphenol, or CHAMP miniature ribbon connector. Although it was invented by Amphenol,^[1] many companies now produce it, such as 3M, TE Connectivity, and Hirose Electric Group.

Two major sizes are available.^{[citation needed]} The larger size has 0.085 inch (2.16 mm) contact pitch. This size, with 36 pins and bail locks, is also known as a Centronics connector because of its introduction by Centronics for use with the parallel port of printers, and is standardized as IEEE 1284 type B. Other connectors of this size are also called Centronics connectors. The smaller size has 0.050 inch (1.27 mm) pitch. This size, with 36 pins, is also known as a mini-Centronics connector, and is standardized as IEEE 1284 type C.

Applications

• 14-pin connector: printer port used on MSX home computers and on various other Japanese computers such as the NEC PC-6000, PC-8800 and PC-9800 series^[2]
• 20-pin connector: VESA Digital Flat Panel digital video interface
• 24-pin connector: IEEE 488 (GPIB, HP-IB) interface ^[3]
• 36-pin connector: IEEE 1284 parallel interface
• 50-pin connector: SCSI-1 interface (SCSI connector)
• 50-pin connector: RJ21X "telco connector" (telephone systems)

See also

• Ribbon cable
• 25-pair color code

References

1. Amphenol Connector Division, Amphenol-Borg Electronics Corporation, Chicago, IL (May 1962). "Why so many?" (PDF). Advertisement. Electronic Industries. Vol. 21, no. 5. Philadelphia, PA: Chilton Company. pp. 126–127. Retrieved 2022-01-23.{{cite magazine}}: CS1 maint: multiple names: authors list (link)
2. Printer port
3. "4". ANSI/IEEE Std 488.1-1987 IEE Standard Digital Interface for Programmable Instrumentation. New York: The Institute of Electrical and Electronics Engineers, Inc. 1988. pp. 67–71.