HOMESite MapContact Us
Global NetworkProductsCorporateInvestor RelationsR & DCSR

Newsletter "SEI NEWS" 2014

Home > Company Information > SEI WORLD > Back number > Vol.438

[Newsletter "SEI WORLD" Vol.438]

Micro Flex Coaxial Cable (MFCX)

Sumitomo Electric developed and started sales of micro flex coaxial cable (MFCX) in 1977. Today the product enjoys the lion's share of the market, maintaining strong sales in Japan and abroad.
The cable employs copper wire rods produced in the Company, the diameter of which is reduced from 8 mm to less than 0.1 mm.

■Product data

Release date May 1997

What is MFCX?

MFCX is a series of micro coaxial communication cables with an outside diameter between 0.20 and 0.35 mm, and is used for basic internal wiring of mobile phones and personal computers. The cables achieve high-speed data transmission as required by electric and electronic equipment today, while their slim and pliable construction allows flexible and downsized packaging.

With increased sophistication in resolution and functions in electric and electronic equipment, faster transmission along with high-frequency properties and noise resistance are required. Our MFCX has many advantages in these requirements over conventional wiring materials such as flexible flat cable.

Structure of MFCX


Where is MFCX used?

Our MFCX is used for internal wiring of various electronic products such as digital cameras, laptop PCs, mobile phones, and flat-screen TVs. Today we offer a wide range of sizes from AWG*36 up to AWG46.

Our Thunderbolt cable also employs MFCX, achieving high-speed data transmission by balancing differential signals with a pair of coaxial wires.

* AWG (American Wire Gauge) is a standard wire gauge system used for the diameters, cross-sectional area, and electrical resistivity of electric wires.

■Interview with engineer in charge
What are the difficulties in manufacturing MFCX?

Tatsunori Hayashishita / Sumitomo (SEI) Electronic Wire, Inc. (SEIW)

MFCX consists of four layers: the core conductor, the dielectric insulator, the shield, and the jacket. To meet customers’ request, we offer a wide range of variations; the finest outsider diameter is 0.2 mm. Each manufacturing process is strictly controlled. For instance, the core conductor is produced by twisting seven copper wires of a diameter of 16 μm with a 15 gram-force breaking strength; the process needs to control tension within 3-5 grams per wire. Meanwhile, the insulating dielectrics and jacket made of fluoroplastic are extruded at a thickness of 20 μm, being controlled within a variation of ±3 μm in outside diameter. To achieve these requirements and continue stable production, we have developed facilities (high-precision low-tension mechanisms), materials (high-tensile conductors and high-flow fluoroplastics) and production management systems (fine-tuned optimum planning, operation, and maintenance).

What features of this product are well regarded by customers?

MFCX attracts customers by its outstanding market advantages including its small outside diameter, high mechanical reliability in movable parts in laptop PCs and mobile phones, high-speed transmission of large-capacity data, and high flexibility.


・Thunderbolt is a trademark or registered trademark of Intel Corporation in the United States and other countries.

2014 Index
(C) 2015 Sumitomo Electric Industries, Ltd.
Using This SitePrivacy Policy