From Impedance to EMC: Full-Process Optimization of Fine Coaxial Cable Termination

In the trend of high-speed signal transmission and equipment miniaturization, micro coaxial cable is widely used in medical equipment, drones, industrial modules, and consumer electronics. It can achieve high-bandwidth transmission within a limited space while maintaining good signal integrity. However, when the cable is terminated with a PCB board, design and process details often determine the final performance.

Impedance Matching and Signal Integrity
Fine coaxial cable束 usually have strict characteristic impedance (commonly 50Ω or 100Ω). If the PCB termination design is not reasonable, it is easy to cause signal reflection, crosstalk, and attenuation. To maintain signal integrity, the trace width, ground plane structure, and via layout should be optimized in the design to ensure impedance continuity and matching.

Two, the reliability of termination technology
The conductor of the micro coaxial cable is extremely thin, and the common termination methods are usually welding or special connectors. The pad size must be precisely matched with the wire diameter, otherwise, false welding or short circuit may occur. If the temperature or time control is not properly handled during the welding process, it may also damage the insulation layer of the wire material. Therefore, the process parameters need to be strictly controlled to ensure that the solder joint is firm and reliable.

Section 3: Mechanical Stress and Fixed Methods
Very thin coaxial cables are soft but rather fragile. If the PCB end is not designed with a reasonable stress relief structure, fractures or poor contact may occur during long-term use. Common optimization solutions include using adhesive reinforcement in the termination area or fixing through structural components to reduce the direct external force acting on the cable.

Four, consideration of Electromagnetic Compatibility (EMC)
The termination location is often the opening point of the shielding layer, and improper handling can easily cause electromagnetic leakage or interference. Optimizing the grounding method and maintaining the continuity of the shielding layer is an important link to ensure the stable EMC performance of the system.

The end design of ultra-fine coaxial cable bundles, although minute, is crucial for the stability and service life of the entire product. Only when electrical matching, process quality, mechanical protection, and electromagnetic compatibility are all well-addressed can the advantages of ultra-fine coaxial cable bundles in high-performance equipment truly be realized.
I am[Suzhou Huichengyuan Electronics], focusing on the design and customization of high-speed signal cables and ultra-fine coaxial cables, committed to providing customers with high reliability and high-performance interconnection solutions. If you have customization requirements or technical consultation, please contact us:Manager Yin 18913280527 (WeChat same number)。