Flat Cables

Flat Cables



Flat cables, sometimes also known as ribbon cables, are a well known name in the field of electronics industry. They are used to interconnect the inner electrical systems especially in computers to connect peripherals. As these cables are flat, they distribute the mechanical load over the total width of the cable. Flat cables help them to increase heat dissipation and thus eliminate the need for large conductors.

Flat ribbon cables consist of highly stranded, individually insulated conductors that are laid parallel and then fused in a flat, flexible ribbon form. These flat cables don't need repetitious insulating material like the traditional round wire cables. The electrical characteristics like capacitance, impedance, attenuation remain uniform because of the uniform geometry in these cables.

Flat Cables

Construction of Flat Cables
Flat cables are typically made of plastic substrates. They have a number of electrical conductors fixed to the plastic substrate. There may be 3 or 4 conductors to more than 50 conductors in a single cable. The axial distance between the adjacent conductors is usually 0.05 inches. The combination of substrate and plastic is flexible and flat. The width of conductors vary according to the device requirement. Plastic substrate are made from different types of plastics. They are:

* Polyester
* Polyvinyl
* Polyamide
* Plyetherimide
* Polyethylene
* Naphthalate
* Polycarbonate

Flat Cable Insulation
A variety of materials is used for insulating the flat cables. Some of the most common and popular in use are:

* Ethylene propylene diene elastomer (EPDM): A chemically cross-linked product which has excellent flexibility at high as well as at low temperatures.

* Fluorinated ethylene propylene (FEP): It is a thermoplastic having strong dielectric properties. Mostly used in high temperature applications and specially in fire-rated cables.

* Polyethylene (PE): A thermoplastic, having a stable dielectric constant. Usually suitable for those applications where low temperature is required.

* Polypropylene: It is similar to polyethylene but is more stiff. Also it has a higher softening temperature.

* Polyvinyl chloride (PVC): It is generally used in non-plenum wire insulation and cable jackets.

* Other Materials: Except all the materials defined above there are certain other materials which are used rapidly. They are polychloroprene, fluropolymers, fluorocopolymers, silicon rubber.

Flat Cable Conductors
Cable conductors are simply wires or group of wires used to carry current from the source to destination. They are not insulated from each other. A variety of materials are used as conductor in flat cables. Aluminum and copper are the two most common metals used for conductors. Aluminum has excellent electrical and thermal properties and is highly resistant to corrosion. It has a density about one-third less than steel, copper, or nickel. On the other hand copper is the extensively used electrical conductor having magnificent corrosion resistance properties and high thermal conductivity.

* Aluminum
* Aluminum alloys
* Aluminum-clad steel
* Copper
* Copper alloys
* Copper-clad steel


Application Industry
Flat cables are commonly used in electrical and electronic equipment. There are a lot of other industries where flat cables are widely used.

* Personal computers and communication equipment.
* Digital and analog tape heads
* Ink jet and dot matrix printer heads
* Connection between the body of laptop computer and its lid.
* Mobile phones
* Medical instruments
* Business machines
* In other consumer electronics and telecommunication industry where small and lightweight flexible cables are required.

Advantages of Flat Cables
Electronic devices are supposed to perform better even in harsh conditions and environments. Flat cables are flexible, thinner, and lighter. Due to these properties the flat cables are the most appropriate for electrical interconnections. The high flexibility of flat cables eliminates the need of group wires. Since these wires are a mess of a number of conductors insulated from each other and they have bending ability. So it is easy to do wiring and other work.