Micro Coax: What are the Common Types of Mini-coax Cables Available?

FACTS CHECKED BY  Jose George​

As cables are demanded in different fields, many cables emerge on the market. Additionally, each cable solution has its specifications and design to cater to the unique application. One variation of Coaxial cable that has growing popularity is the micro coax cable. However, what is it, and how many types are found in the market? Let us find out.

4k HDMI Cable | Working Principle |...
4k HDMI Cable | Working Principle | Normal Vs HDMI cable

What are Micro coaxial cables?

Mini-coax or micro-coax is the cable type because it has a small outer diameter. This small, lightweight coaxial transmitter cable has a 50-Ohm characteristic impedance and low capacitance and signal loss. You can also use it in devices that need a wide array of high-frequency connection signals, especially if there are hinges or other parts that move.

Also, it is beneficial in situations where there is not a lot of space. Thus, depending on what type of micro-coax, it has a stranded center conductor and a single or dual insulated outer layer. 

To use micro-coax with other interfaces, you can use MMCX connectors. To explain, these MMCX connectors are small micro coaxial connectors that mate with a locking system and can be rotated at their link. Moreover, these coax contacts can handle frequencies up to 6 GHz. Additionally, they have 50-Ohms impedance and can take them. You can also use it along with antennas inside the device or make it easier to connect outer conductors in industrial automation.

F connector Micro cable

Caption: F connector Micro cable

Types of Micro coaxial cables

Usually, they are grouped by how big their outside diameter is in millimeters:

  • 1.13 mm to 1.32 mm
  • 1.37mm

1.13mm coaxial cable

For U.FL cables, the most common coax is RG6. But, in the case of MHF4 cables, there is only one coax you can use, which is 1.13.

Thus, when you need to connect a U.FL plug to a jack to a mini-PCI card or board, you might need to use a 1.13mm cable. It is because the 1.13 cables are thin yet stretchable. However, It’s not always essential to use a 1.13mm cable, but when you want to keep the U.FL connector from trying to come off the jack, a 1.13 cable is needed. 

A 1.13mm cable with a 50 Ohm resistance can vary by 3 Ohm. Also, it is a single protected coax cable with an FEP jacketing.

Some significant features include

  • The smaller cable diameter of 1.13mm (0.04 inches), whereas the AWG is 32. Moreover, it is a silver-plated copper core with no polymer dielectric.
  • A low loss 1.13 types of coax have an insulation material binder made of copper polyester tape, which helps to shield.
  • The optimal VSWR is between 0 to 6 GHz, up to the maximum point of 6 to 8Ghz. The best frequency is 6GHz.

1.32mm coaxial cable

It is also a single shielded cable made with silver-coated copper material. Moreover, it has FEP jacketing to cover the cable on the top. Some key features include

  • The dielectric diameter is 0.70 mm (0.028 inches).
  • There is a conductor diameter of 0.22mm in this cable, and the AWG of the cable is 32. Moreover, the core is of silver-plated solid copper in the middle.
  • Coverage of the shielded braid may be less than 90%. 
  • Coaxial cable with two layers of silver-coated copper braid is called double shielded. This version has two layers of braid, with the second layer covering 78% of the cable.
  • Conductor resistance is 850Ohm/km but lower insulation resistance than RG178 at 1000Ohm/km.
  • VSWR is the at 1.3, between 0 and 6 GHz. The best frequency is 6 GHz.

1.37mm micro coaxial cable

 1.37mm coaxial cables have the same signal loss as RG174 and RG178 mini coaxial cables, but they are thinner and easier to bend. Moreover, the 1.37mm has the same shape conductor as the RG178 cable but with a smaller diameter. They stay on because it is among the flexible cables, and since it fits into minimal space better than other types of wire, they are more suitable than the RG174 or RG178. 

RG174

RG174 cables have 50 Ohms resistance (with a difference of 2 Ohms). Unlike 1.13 or 1.32 cables, it is a single shielded cable with a tinned copper braid. Some common features include

  • It contains non-polymer dielectric, usually Polyethylene (PE) material. Also, the insulation is almost double the amount of diameter in it.
  • The stranded central metalcore has nearly seven strands of copper-clad steel and is still bound to a small diameter.
  • There is jacketing of PVC material on it. 
  • The diameter is greater than RG178 ( up to 2.79 mm or 0.11 inches) but has a lower AWG rating (26 AWG).
  • Its conductor resistance of 142 Ohms/km but has higher insulation resistance at 1000 Ohms/km.
  • The optimal frequency range is 2.4Hz.

RG178 

RG 178 is a very thin cable and has a lot of resistance to heat (operating temperature ranges from -55 to 200 degrees Celsius or -67 to 392 degrees Fahrenheit). Thus, you can opt for it in high-frequency transmissions. Moreover, RG178 coax cable can be used for 

  • Internal Cabling
  • Television and CCTV
  • Wireless communications and networking
  • Testing and measurements
  • Telecommunications and broadband

Micro Coaxial Cable Assemblies At Gloom

Gloom Tech makes and elongates a wide variety of quality interconnection solutions, mostly used on PCB solutions and other reduced termination points that need to carry important signals. Both small and big custom orders can be made for custom lengths of wire, connectors, EMI and RFI shielding, wire jacket types, and more.

Standard Mini Coax Cable Assemblies

Some features of micro-coax that our company provides are

  • Available with SSMA, MMCX, IPEX, Murata, or SSMP boarding level plugs
  • With our micro-coax assemblies, you can experience a direct contact-to-board connection accessible with 0.175mm pitching.
  • Moreover, there are many connection configurations, like SMA to MMCXs, MHFs to SMAs, MHFs to MHFs, and G4POs to SMAs connectors.

Mostly, we take the lead time for custom order configurations.

Molded Mini Coax Cable Assemblies

In addition to being accessible as a plug and socket, you can crimp the Mini Coax wire connector to a coax cable. It is so that you can independently build with RF connectors (like SMA, SMB, N-type, etc.)

Moreover, the molded Mini Coax wire assembly provides an excellent RF transmission rate, and the connections made with them are strong and reliable. Cable assemblies manufacturer companies produce various angle mold types to satisfy various cable routing requirements, depending on available space. Yet, it is possible to meet unique connecting needs with the help of a variety of accessories such as backplane frames, housing inserts, and press-in cable housings, among other things.

Bundle of Coaxial Cable

Caption: Bundle of Coaxial Cable

Conclusion

Micro or mini coax cables have a small diameter. Still, they can transfer up to 50 Ohms of impedance with lower capacitance and signal loss. In markets, you can find the variation of coax cables as 1.13mm, 1.32mm, 1.37mm, RG174, and RG 178. Here at Bloom, we offer custom coax cables, so your connection is made with attention to detail.

Get a free Cable Assembly Quote.