As living standards continue to rise, the economic boom has enabled more people to afford cars. When selecting a vehicle, have you ever considered the connectors used in the car parts? Automotive connectors are typically high-speed connectors, and when developing high-frequency vehicle connection systems, the primary design considerations are accuracy, mechanical strength, and overall suitability in harsh environments. To achieve interference-free data communication through cables and interfaces for symmetrical high-frequency electrical signals, the following five characteristics are crucial.

Constant impedance on transmission lines

2. Insulating material has low dielectric loss.

3. The connectors feature excellent low-resistance terminal connections.

4. Pair Signal Wire Twisting Rule

5. Eliminated some duplicate coverage.

Inside the vehicle, signals are transmitted through shielded USB cables to the relevant USB control units, such as the "main unit." This connection method has been tested against various automotive application specifications. Under complete shielding, this connector also meets the 480MBit/s high-speed USB transmission standard. This ensures the stability of impedance from the USB interface to the control unit and good electromagnetic compatibility.

Electromagnetic compatibility (EMC) performance is also crucial for the quality of connector technology. To demonstrate this performance, the USB interface in operation has been tested in accordance with the relevant EMC standards. Considering the data transmission speed, a corresponding high-speed USB data transmission system should be developed based on high-frequency parameters. Some key high-frequency parameters from the SAE/USCAR-30 draft/08-2006 specification regarding the USB 2.0 revision include the following five points:

Impedance Range: (90 ± 15%)

2. Propagation Delay (<26ns)

3. Propagation Time Delay (<100ps)

4. Attenuation rate (<5.8dB, f=400MHz)

5. Shielding Range (minimum 20dB, 30MHz to 1GHz).

Impedance discontinuities in the transmission path can lead to reflection losses and signal distortion. With Time-Domain Reflectometers (TDRs), impedance values can be directly displayed as a function of time, allowing for real-time monitoring to ensure they meet the system tolerance specifications of the USB system. In addition to these parameters, attenuation rate is also a critical nominal value that can significantly impact interconnect attenuation, which can cause signal distortion and affect system power design.

Electronic data links must fulfill two main tasks: data transmission and non-interference with the surrounding environment. Therefore, it is crucial to ensure adequate shielding of wires and connectors, as well as low inductive interconnection between connectors and their shielding. Shielding effectiveness parameters reveal the shielding quality of passive components such as connectors, cables, and connector assemblies. Shielding effectiveness provides a removable parameter range for electromagnetic interference. Minimizing radiation values and maximizing resistance to interference not only depend on the design of the connectors but also on the concept of connection between the shielding layers.