What Is a Micro Ribbon?

A micro ribbon is an electrical connector for multiple signal cables. Electrical signal connectors have to be reliable and easy to connect and disconnect for installation and maintenance. Also called a telco or Amphenol® connector, the micro ribbon is a miniature ribbon connector with two rows of connector pins that have a polarized geometry to maintain correct one-to-one pins connections. For instance, if somebody disconnects the connector and rotates it 180 degrees, it should not fit in the micro ribbon socket because it is polarized. Other names for the micro ribbon are delta ribbon and CHAMP® connector.

In telecommunications, the 25-pair micro ribbon is indispensable in cabling management. For instance, in telephone distribution equipment, dealing with 1,000 subscribers is helped by dealing with only 40 cables, which are 25 pairs. These cables usually have micro ribbon connectors on each end. The micro ribbon is vital in implementing hierarchical wire-pair management.

A ribbon cable is a flat-type cable that has several insulated conductive wires arranged side by side. The first ribbon cables were common for interconnecting digital buses that usually require at least a dozen to as much as 100 wires. Ribbon cables are usually made of stranded, tinned copper wires. The insulation may be a single color or color-coded to aid the installers when connecting wire by wire. In most cases, however, there are equipment-side connectors and cable-side connectors that are either machine-installed or aided by special mounting and crimping tools for rapid production of multi-pair cables.

Single-ended digital signal connections may use short lengths of ribbon cables for low speed. These signals are usually between 0 and 5 volts direct current (VDC). For high-speed digital data and control, there may be single-ended signal wires that toggle between –5 and +5 VDC. The latter may still use a common wire or a return wire. When speed and resilience from interference are needed, the single-ended output is replaced with a double-ended signal format that uses a twisted pair of wire.

Whether to use single wires or wire pairs depends on the nature of the signal drivers of the equipment. For telecommunications use, the signals are usually double-ended or balanced. This means the signal is in a pair of wires and each wire in the pair is driven by a signal that is the opposite phase of the other. These types of signals use twisted pair cables that maintain a sufficient electromagnetic confinement or shielding of the signal in the pair; the more twists per inch, the better the shielding. The reciprocal benefit is that electromagnetic noise from the outside, or from another pair, is not induced into the wire pair.