Is there an extremely thin coaxial cable inside the USB4/Thunderbolt cable? Unraveling the secret behind high-speed transmission

In the era of high-speed data transmission, USB4 and Thunderbolt cables are widely used in computers, monitors, and various high-performance devices. However, many people may wonder: do these cables really use extremely thin coaxial cables? Although it is difficult to identify directly with the naked eye, we can make a reasonable judgment through the transmission speed, flexibility, interface characteristics, and internal structure.

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The necessity of transmission rate and miniature coaxial cables

USB4 and Thunderbolt 5 interfaces have bandwidths of up to 40Gbps or 80Gbps, which is difficult for ordinary multi-strand twisted wires to maintain such high speeds over long distances. If a cable claims to support full-speed USB4 or Thunderbolt protocols, its key differential pairs are likely to use extremely thin coaxial cables to effectively reduce crosstalk and signal attenuation, thereby ensuring high-speed stable transmission.

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Diameter, flexibility and hand feel

High-speed cables with extremely fine coaxial cores usually have an outer diameter slightly larger than that of ordinary USB cables, but they are more flexible. The shielding layer and dielectric material of the micro coaxial cable are highly consistent, making the cable feel smooth when bending and allowing for more flexible cabling. Compared to multi-strand twisted wires, the micro coaxial cable performs more stably and reliably in small spaces and high-density cabling.

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Section 3: Interface Function and Internal Structure Characteristics

Cables supporting the complete Thunderbolt protocol can achieve the three-in-one function of data, video, and power supply, and this multi-signal mixed transmission is an advantageous application scenario of extremely thin coaxial cables. Disassembling the cable reveals that the USB4/Thunderbolt cable set with micro coaxial cable contains numerous independent insulated micro coaxial cables wrapped in shielding layers, with diameters generally around 0.3~0.5mm, arranged closely to ensure high bandwidth and stability.

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To determine whether USB4 or Lightning cables use ultra-fine coaxial cables, one can infer by combining factors such as transmission speed, flexibility, functional characteristics, and internal structure. For applications that seek high speed, stability, and high compatibility, micro coaxial cable has become an indispensable solution.

I am[Suzhou Huichengyuan Electronic Technology], Long-term focused on the design and customization of high-speed signal cables and extremely thin coaxial cables, committed to providing stable and reliable high-speed interconnection solutions. If you have any related needs or want to learn more, welcome to contactManager Zhang: 18913228573 (same as WeChat)。