As electronic devices develop towards being thinner and more multifunctional, the design of the internal connection system becomes increasingly compact. The extremely fine coaxial cable (micro coaxial cable) boasts excellent anti-interference performance and stable high-speed transmission capabilities, and is widely used in laptop computers, vehicle-mounted cameras, industrial cameras, medical equipment, and other fields. However, due to the thin diameter, large quantity, and high termination density of the extremely fine coaxial cable, its arrangement process presents many challenges to the production process.
Technical difficulties in the arrangement of extremely fine coaxial cable bundles
In practical applications, the arrangement of extremely fine coaxial cable bundles mainly faces the following technological difficulties:
High-density arrangement requirements
The diameter of a single micro coaxial cable is usually between 0.3mm and 0.6mm. To meet the demand for compact layout within the equipment, the cable bundle needs to be densely arranged with extremely small spacing. Any deviation may cause signal interference or short circuit.
High terminal crimping accuracy
The internal structure of extremely thin coaxial cables is complex, and it is necessary to ensure that the shield layer, insulating layer, and conductor stripping length are consistent. When welding terminals, the temperature and pressure must be uniform and appropriate to avoid damaging the core wire and ensure signal integrity.
• Strict welding process requirements
The焊points are extremely small, and the temperature and time for welding need to be controlled precisely. Too high a temperature may damage the insulation layer, while too low a temperature may result in unreliable welding, directly affecting the product's performance and stability.
• 屏蔽层处理复杂
Micro coaxial cable is usually equipped with a braided or foil shield. During the stripping and welding process, it is necessary to ensure that the shield layer is intact and well connected to ground, otherwise it is prone to signal interference or EMI exceeding the standard.
Strict requirements for molding and fixation
Extremely thin coaxial cable bundles are soft and easily deformed, requiring processes such as potting, heat shrinkage, or sheathing, as well as reasonable fixation design, to prevent cable loosening or interference with other electronic components.
Section 2: Advantages and Introduction of KEL USL20-30S Connector
In the ultra-fine coaxial cable assembly scheme, Japan's KEL brand USL20-30S connector is widely recognized and commonly used in high-end equipment such as notebook camera modules, vehicle-mounted imaging, and industrial cameras. The main features are as follows:
Series positioning
KEL USL series, designed specifically for AWG#42 micro coaxial cable, with 0.4mm spacing IDC (insulated displacement connector) connectors.
Physical structure
Plug-end straight-line design, compatible with 30Pin (USL20-30S) arrangement, convenient for high-density wiring.
Material and electrical properties
The insulator uses glass fiber reinforced LCP (UL94V-0) black material, the metal shell and terminals are made of copper alloy, and the surface is gold plated over nickel.
Standard Application
Suitable for high-speed LVDS signal transmission, widely used with camera modules and industrial vision equipment from brands such as Sony and Tamron.
It is noteworthy that the domestic substitution solutions have already reached a high level of maturity in terms of processing technology, connection reliability, and cost control, and possess a significant competitive advantage.
Although there are challenges in the arrangement of extremely fine coaxial cable bundles, combining mature production processes with high-quality connector products can fully meet the needs of high-speed and high-density connections for high-end equipment. Choosing a mature domestic alternative solution can not only ensure stable performance but also reduce costs and improve delivery efficiency.
We have been focusing on the design and customization of high-speed signal cable harnesses and ultra-fine coaxial cable harnesses for a long time, committed to providing stable and reliable high-speed interconnect solutions. If you have any related needs or would like to learn more, please contact: Manager Yin.
18913280527（WeChat same number）. 
