Automotive high speed connector design knowledge
People's living standards have been constantly improving, and the economic level has improved, so that more people have the money to buy cars. When you buy a car, have you ever thought about the connectors used in these car parts? The connector products used in automobiles are mostly high-speed connectors. When developing high-frequency vehicle connection systems, the design issues of accuracy, mechanical strength and overall applicability when used in harsh environments are first considered. If you want to achieve symmetrical high-frequency electrical signals through the cable and interface for interference-free data communication, the following five characteristics are very important.
1. Constant impedance on the transmission line;
2. The dielectric loss of the insulating material is small;
3. The connector is connected by a good low resistance terminal;
4. Paired signal wires are regularly stranded;
5. Shield part of the repeated coverage.
The in-vehicle signal is transmitted to the associated USB control unit via a shielded USB cable, such as a "main unit." This type of connection is tested by various automotive application specifications. In the case of complete shielding, this connector can also meet the USB high-speed transmission standard of 480MBit/s. This ensures the stability of the USB interface to the control unit impedance and good electromagnetic compatibility.
Electromagnetic compatibility is also critical to the quality of the connector technology. To demonstrate this performance, the USB interface in operation has been tested according to the corresponding EMC standards. Considering the data transmission rate, the corresponding USB high-speed data transmission system should be developed according to the high-frequency parameters. According to the SAE/USCAR-30 draft 08-2006 specification, some of the main high frequency parameters of the USB2.0 revision are as follows:
1. Impedance range (90 ± 15%);
2. Propagation delay (<26ns);
3. Propagation delay difference (<100ps);
4. Attenuation rate (<5.8dB, f=400MHz);
5. Shielding range (minimum 20dB, 30MHz~1GHz).
Impedance discontinuities in the propagation path will result in reflection losses and signal distortion. With the Time Domain Reflectometry (TDR), the impedance value can be displayed directly as a function of time to monitor whether the value meets the specified system tolerances of the USB system. In addition to these parameters, the attenuation rate is also one of the nominal values that have a significant impact. Interconnect attenuation will cause signal distortion and affect the power design of the system.
The electronic data link must accomplish two main tasks: one is data transmission, and the other is that it does not affect the surrounding environment. Therefore, care must be taken to ensure that the wire and connector shields and the extremely low inductive interconnection between the connector and the connector shield. By shielding the performance parameters, it can be seen that the shielding quality of passive components such as connectors, cables and connector components provides a range of parameters that can be eliminated by electromagnetic interference. The minimization of absolute radiation values and the maximization of immunity to interference depend not only on the design of the connector, but also on the concept of the connection between the shielding layers.
1. Constant impedance on the transmission line;
2. The dielectric loss of the insulating material is small;
3. The connector is connected by a good low resistance terminal;
4. Paired signal wires are regularly stranded;
5. Shield part of the repeated coverage.
Electromagnetic compatibility is also critical to the quality of the connector technology. To demonstrate this performance, the USB interface in operation has been tested according to the corresponding EMC standards. Considering the data transmission rate, the corresponding USB high-speed data transmission system should be developed according to the high-frequency parameters. According to the SAE/USCAR-30 draft 08-2006 specification, some of the main high frequency parameters of the USB2.0 revision are as follows:
1. Impedance range (90 ± 15%);
2. Propagation delay (<26ns);
3. Propagation delay difference (<100ps);
4. Attenuation rate (<5.8dB, f=400MHz);
5. Shielding range (minimum 20dB, 30MHz~1GHz).
Impedance discontinuities in the propagation path will result in reflection losses and signal distortion. With the Time Domain Reflectometry (TDR), the impedance value can be displayed directly as a function of time to monitor whether the value meets the specified system tolerances of the USB system. In addition to these parameters, the attenuation rate is also one of the nominal values that have a significant impact. Interconnect attenuation will cause signal distortion and affect the power design of the system.
The electronic data link must accomplish two main tasks: one is data transmission, and the other is that it does not affect the surrounding environment. Therefore, care must be taken to ensure that the wire and connector shields and the extremely low inductive interconnection between the connector and the connector shield. By shielding the performance parameters, it can be seen that the shielding quality of passive components such as connectors, cables and connector components provides a range of parameters that can be eliminated by electromagnetic interference. The minimization of absolute radiation values and the maximization of immunity to interference depend not only on the design of the connector, but also on the concept of the connection between the shielding layers.
After reading the above, you should have a basic understanding of the car telling the connector design knowledge, more articles related to the car high-speed connector, our engineers will continue to organize and publish on the information channel, interested users can pay more attention The latest news on our website.
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