Overview
Micro coaxial cable (typically with outer diameters smaller than 0.5mm) is high-frequency transmission lines optimized for space-constrained applications in medical devices, consumer electronics, industrial sensors, and aerospace systems. These cables excel in delivering low-loss signal integrity and robust electromagnetic interference (EMI) shielding at submillimeter scales.
Structural Analysis
A micro coaxial cable features a multi-layered design engineered for precision and durability (illustration suggestion: labeled cross-sectional diagram):
1. Inner Conductor
- Material: Silver-plated copper or high-strength copper alloy
- Diameter: 0.02–0.1mm
- Function: Transmits high-frequency signals; silver coating minimizes skin effect losses at GHz frequencies.
2. Dielectric Layer
- Material: Foamed polyethylene (PE), polytetrafluoroethylene (PTFE), or low-density fluoropolymer
- Thickness: 0.05–0.15mm
- Function: Electrically isolates inner and outer conductors; reduced dielectric constant enhances signal velocity.
3. Outer Conductor
- Material: Combination of aluminum foil and silver-plated copper braid
- Structure: Helically wound or multi-axis braided shielding
- Function: Blocks external EMI and provides a low-impedance return path for signal currents.
4. Protective Jacket
- Material: Flexible polyurethane (PU) or thermoplastic elastomer (TPE)
- Thickness: 0.03–0.1mm
- Function: Resists abrasion, chemicals, and repeated bending while maintaining electrical insulation.
Key Performance Advantages (illustration suggestion: performance comparison charts)
- High-Speed Transmission: Supports frequencies up to 40 GHz, enabling 5G mmWave, USB 4.0, and high-resolution video signals.
- Space Efficiency: Outer diameters as small as 0.13mm (e.g., Hitachi’s 0.13mm micro-coax) allow integration in endoscopic tools and foldable displays.
- Durability: Withstands over 200,000 bending cycles (tested per IEC 60601 standards for medical use).
- EMI Immunity: Dual-layer shielding achieves >90% noise suppression in densely packed electronic assemblies.
Typical Applications (illustration suggestion: annotated use-case diagrams)
- Medical:
- Real-time signal transmission in cardiac catheters and neurostimulation probes.
- Endoscopic imaging systems requiring sub-0.3mm cables.
- Consumer Electronics:
- Interconnects for TWS earbuds, smartwatch sensors, and foldable smartphone hinges.
- High-speed data links in AR/VR headsets.
- Industrial & Aerospace:
- Micro-camera wiring for pipeline inspection robots.
- Satellite payloads requiring lightweight, high-density cabling.
Manufacturing Challenges
- Precision Extrusion: Sub-micron tolerance control during dielectric layer coating.
- Shielding Complexity: Balancing flexibility and shielding effectiveness in sub-0.5mm designs.
- Testing & Certification: High-frequency characterization (e.g., insertion loss <0.5dB/cm at 10GHz) and biocompatibility testing for medical use.
Future Trends
Advancements in nano-coating technologies and liquid crystal polymer (LCP) dielectrics are pushing micro coaxial cables toward thinner profiles (<0.1mm) while maintaining GHz performance. These innovations will further enable next-generation implantable medical devices and wearable electronics.
Visualization Recommendations:
- Cross-Sectional Diagram: Highlight layer materials and critical dimensions (e.g., 0.02mm inner conductor vs. 0.1mm jacket).
- Bend Test Animation: Demonstrate flexibility in medical catheters or folding smartphone hinges.
- EMI Shielding Demo: Compare signal integrity with/without shielding in a noisy environment.
- Industry-Specific Icons: Medical (endoscope), consumer (TWS earbuds), aerospace (satellite).
(Note: For technical documents, align terminology with industry standards such as IEC 61196 for coaxial cables.)
No responses yet