<p id="04d6h"><del id="04d6h"></del></p>

    <table id="04d6h"></table>

    <td id="04d6h"></td><track id="04d6h"><strike id="04d6h"></strike></track>


      National service hotline0769-38895658
      Your current location:

      High-speed connector quality inspection focus! How much do you know?

      source:YUAN TAI ELECTRICAL CO .,LTDrelease time:2018.10.17 17:17:23 attention:1,312

      Under the vigorous development of the communication industry, various electronic products continue to pursue a larger and more stable transmission quality, and the timeliness of data transmission and diversified application requirements have also promoted the development of high-speed signal transmission technology. In order to improve the signal transmission speed, in addition to changing the signal coding mode, it is an improved way to reduce the signal level or provide a full-duplex transmission mode.


      At the same time, the requirements for reducing signal attenuation and distortion and avoiding noise interference between components or devices are greatly improved. Therefore, connectors as communication bridges are also very important, and the influence of transmission speed on the quality and performance of transmission signals is also receiving increasing attention. .

      USB data transfer from the early USB 1.0 maximum transfer speed of 12 Mbps, USB 480 Mbps, USB 3.1 Gen 1 5 Gbps, all the way to USB 3.1 Gen 2, not only the transmission speed increased to 10 Gbps, its communication The mode has also been upgraded from half-duplex to full-duplex to meet the increasing demand for high-speed transmission.


      In appearance, in recent years, driven by smart phones, the USB interface has been used in a wide range of standard A, B Type, Mini series, and Micro series products, as well as the recently popular USB Type-C. With a reduction of 6 times, the trend of consumer electronics is becoming lighter and thinner. The future of the connector industry is bound to move toward a light, short, and fast transmission efficiency.

      Allion Shenzhen Laboratories has been authorized by the USB Association (USB-IF) to become the only officially authorized USB cable and connector lab in China, providing compatibility testing and technical consultation of USB cables and connectors. At present, there are many key projects in the development process of USB 3.0 and USB Type-C cables and connectors. We will analyze the problems and problems that manufacturers are likely to encounter, provide corresponding quality inspection focus, and hope to assist manufacturers in the product development process. The middle can be smoother and more efficient.

      Significantly improved transmission performance

      Since early low-speed connectors do not need to provide a large amount of signal transmission, the electrical performance of the connector requires only direct current conduction or not, and mechanical performance is the focus of testing, such as insertion force, plug-in life, terminal retention and contact. Resistance testing, etc., because these tests have an impact on mechanical and electrical performance. After entering the year 2000, USB and IEEE 1394 came out one after another, announcing that the connector entered another era. The purpose of the connector was to only require the current to be turned on to the transmission of a large number of signals, and the signal integrity became the focus of measurement. In the future, the integrity of the signal can be verified through test items such as Impedance, Propagation Delay, Propagation Skew, Attenuation, Crosstalk, and Crosstalk.

      High-frequency signal test focus 1: string sound measurement (Crosstalk)

      With the massive transfer of data, high-frequency connectors such as HDMI, DisplayPort and USB 3.1 Type-C have been introduced, and the transmission speed of connectors has also increased from Mbps to Gbps. When the signal speed continues to increase, how to reduce noise interference has become an important issue. Therefore, the single-line transmission architecture is gradually converted into a Shielded Twisted-Paired, even with a coaxial type (Coaxial), thereby reducing the noise itself. The generation and improvement of the ability to resist external interference; but because of the influence of multiple or more pairs of signals at the same time high-speed transmission, the degree of crosstalk is gradually increasing, so the generation of various crosstalk phenomena (Crosstalk) must be analyzed and discussed.

      Crosstalk refers to the coupling of radiated signals between two signals. This is because the distance between the signal pairs is adjacent, and the radiated signals are mutually coupled by the stray inductance and the stray capacitance between the two, and the capacitive coupling causes the coupling current, and the inductive coupling causes the coupling voltage; In real life, for example, when a home phone is on a call, it occasionally hears a third party due to crosstalk interference. Generally speaking, when high-frequency signals are transmitted on adjacent signal lines, it is difficult to avoid the occurrence of crosstalk interference. Therefore, it is necessary to use the serial volume measurement to know whether the crosstalk interference is controlled within an allowable range. Crosstalk can be divided into two types: Near End Cross Talk (NEXT) and Far End Cross Talk (FEXT). Currently, Type-C has 4 pairs of signal pairs, and DisplayPort has multiple control signals. The AUX channel used has a total of 5 pairs of signal pairs. The two industries (which should be changed to the industry in the case of mainland usage) all attach great importance to the measurement of crosstalk parameters; and also include crosstalk testing in one of the verification projects.

      High-frequency signal test focus 2: signal loss measurement (Loss)

      Along with the development trend of miniaturization of products, the demand for light and recyclable wire in the cable set used in the connector is greatly increased, and the core wire diameter is bound to become finer and finer. At present, the HDMI cable is about 24~30 AWG, and the USB 3.1 is 28~34 AWG. The AWG is the American wire gauge, which is a standard for distinguishing the wire diameter. The larger the value, the smaller the wire diameter and the smaller the conductor, which is transmitted online. The high-frequency signal will be more affected by the characteristics of the conductor itself, and the industry standard association will usually set an acceptable frequency loss reference standard in the specification.

      Loss refers to the degree of attenuation of the signal in the transmission line. The types of loss can be divided into: Insertion Loss and Return Loss. In the ideal state, the transmission of the signal is not attenuated; in fact, the longer the transmission distance is affected by the characteristics of the copper material, the more the signal loss (ie, the larger the loss of the line group), the higher the insertion frequency decreases with the frequency of the signal. The resulting signal loss is also greater, although this conductor loss has little effect on the connector itself, but it has a profound effect on the cable set.

      The generation of reflection loss mainly occurs in the connector itself or on the mating interface, because the shape and characteristics of the connector itself are difficult to form a so-called "transmission line structure", and the series connection between the cable and the connector bonding process will also Causes a large amount of reflection loss of the signal. In order to effectively control the loss of transmission line without affecting quality, the measurement of Insertion Loss and Return Loss is an indispensable item for verifying high frequency connectors in the future.

      Wire loss testing needs to be done by instrument. Generally speaking, the device for measuring wire loss includes two test devices, Time domain and Frequency domain. Taking USB as an example, the Time Domain Reflectometry (TDR) and the Network Analyzer (NA) are required for the USB 3.1 certification test. The two devices measure different parameters. The increase of transmission speed has considerable challenges for measurement equipment. The construction of complete measurement equipment needs to be updated with the change of technology, and the cost is gradually improved. How to establish an effective test environment is also very large for manufacturers. burden.

      Taking USB 3.1 Type-C authentication as an example, the equipment vendors that can be used to verify the loss of the numbers have different operation directions. Generally speaking, the MOI (Method of Implementation) proposed by the equipment manufacturers all use a single machine. Complete the cable set test project. That is, the time domain and frequency domain tests are performed on a single machine. On Tektronix's TDR, TDR converts measured time-domain signals into fast-Fourier Transforms (I) through IConnect software and converts them into sin waves in different frequency domains. In addition, Keysight's ENA uses the option TDR function to convert the measured frequency domain signals into time domain signals through Inverse Fourier Transform. Through the auxiliary conversion of the software, the tester can simultaneously measure the frequency domain and the time domain signal, and quickly complete the required measurement items, and also greatly reduce the company cost. It also simplifies the time for engineering staff to analyze.


      Figure 4 Time domain and frequency domain signal diagram

      Light and thin, meeting a large number of data transmission needs, is the inevitable trend of connector development in the future, the connector industry has been freed from the traditional mode of mechanical processing towards microwave components and high-frequency characteristics. In order to maintain a high degree of competitiveness and produce high quality products, the ability from cable design to measurement and result analysis has gradually created a watershed in industrial development. How to improve the ability to move toward the high unit price of board to board It will be the key technology for the connector manufacturers to upgrade upwards. The major cable connector manufacturers have invested a lot of research manpower, and pay attention to the product verification test to establish the quality and popularity of their own products.

      Article copyright note

      Article copyright Yuan Tai all
      Article link:http://www.kwnotes.com/en/3264.html
      Unauthorized, it is forbidden to mirror, collect, or copy the contents of this site, and the offenders will defend their rights through legal channels!
      Cooperation withYuan Tai

      General process

      Unified national service hotline

      Consult now

      Yuan TaiProduct development technology center,strong strength

      R&D team with more than ten years of product excellence
      Thanks to the following strategic partners for their long-term support for
      Yuan Tai  for more than ten years.
      Thanks to the following strategic partners for our support
      • Superflower
      • Seasonic
      • Quanhan Power
      • Huntkey
      • Liteon
      • CHIGO
      • ACBEL
      Grasp every process and do every product >>>>>>>>
      Improve after-sales service quality and improve customer satisfaction

      Survive by quality, develop by credit, meet contract requirements and potential needs!

      National Advisory Hotline

        <p id="04d6h"><del id="04d6h"></del></p>

        <table id="04d6h"></table>

        <td id="04d6h"></td><track id="04d6h"><strike id="04d6h"></strike></track>