Basic performance and benefits of connectors
Mechanical performance. As far as the connection function is concerned, the insertion and extraction force is an important mechanical performance. The insertion and extraction force is divided into the insertion force and the extraction force (the extraction force is also called the separation force). The requirements of the two are different. In the relevant standards There are regulations for maximum insertion force and minimum separation force, which shows that from the perspective of use, the insertion force should be small (there are low insertion force LIF and no insertion force ZIF structure), and if the separation force is too small, it will affect the contact The reliability, insertion and extraction force and mechanical life of the connector are related to the contact structure (the size of the positive pressure of the connector) the coating quality of the contact part (the sliding friction coefficient) and the dimensional accuracy of the contact arrangement (alignment).
Basic performance and benefits of connectors
Electrical performance The main electrical performance of the connector includes contact resistance, insulation resistance and dielectric strength.
1. High-quality electrical connectors with contact resistance should have low and stable contact resistance. The contact resistance of the connector ranges from several milliohms to tens of milliohms.
2. Insulation resistance is an index component that measures the insulation performance between the contacts of electrical connectors and between the contacts and the shell, and its magnitude ranges from hundreds of megaohms to several thousand megaohms.
3. Dielectric strength, or withstand voltage, dielectric withstand voltage, is the ability to withstand the rated test voltage between the connector contacts or between the contacts and the shell.
4. Other electrical properties.
Electromagnetic interference leakage attenuation is to evaluate the electromagnetic interference shielding effect of the connector, and the electromagnetic interference leakage attenuation is to evaluate the electromagnetic interference shielding effect of the connector, and it is generally tested in the frequency range of 100MHz~10GHz.
For RF coaxial connectors, there are electrical indicators such as characteristic impedance, insertion loss, reflection coefficient, and voltage standing wave ratio (VSWR). Due to the development of digital technology, in order to connect and transmit high-speed digital pulse signals, A new type of connector is a high-speed signal connector. Correspondingly, in terms of electrical performance, in addition to characteristic impedance, there are also some new electrical indicators, such as crosstalk, transmission delay, and skew. )Wait.
The common environmental performance of the ring electronic connector includes temperature resistance, humidity resistance, salt spray resistance, vibration and impact.
1. Temperature resistance At present, the maximum working temperature of the connector is 200°C (except for a few high-temperature special connectors), and the minimum temperature is -65°C. When the connector is working, the current generates heat at the contact point, resulting in temperature rise, so it is generally It is believed that the working temperature should be equal to the sum of the ambient temperature and the temperature rise of the contact. In some specifications, the maximum temperature rise allowed by the connector under the rated working current is clearly specified.
2. The intrusion of moisture resistance of industrial connectors will affect the insulation performance of the connection h and rust the metal parts. The constant humidity test conditions are 90%~95% relative humidity (according to product specifications, up to 98%), temperature +40±20℃ , The test time is 96 hours at least according to the product regulations, and the alternating damp heat test is more stringent.
3. When the salt spray resistant connector works in an environment containing moisture and salt, the metal structural parts and the surface treatment layer of the contact parts may produce galvanic corrosion. The board-to-board affects the physical and electrical properties of the connector, in order to evaluate the electrical connection The ability of the device to withstand this environment stipulates the salt spray test, which is to hang the connector in a temperature-controlled test box and spray a sodium chloride solution with a specified concentration with compressed air to form a salt spray atmosphere. The exposure time is specified by the product specification and is at least 48 hours.
4. Vibration and shock Vibration and shock resistance is an important performance of electrical connectors. It is particularly important in special application environments such as aviation and aerospace, railway and road transportation. It is used to test the robustness and mechanical structure of electrical connector pin headers. Important indicators of electrical contact reliability are clearly defined in the relevant test methods. The peak acceleration, duration and shock pulse waveform, as well as the interruption time of electrical continuity, should be specified in the impact test.
5. Other environmental performances According to the requirements of use, other environmental performances of electrical connectors include airtightness (air leakage, liquid pressure), liquid immersion (resistance to specific liquids), low air pressure, etc.
1. Improve the production process
The serial female connector simplifies the assembly process of electronic products and also simplifies the mass production process;
2. Easy to repair
If an electronic component fails, the failed component can be quickly replaced when the connector is installed;
3. Easy to upgrade
With the advancement of technology, components can be updated when connectors are installed, and new and more complete components can be used to replace the old ones;
4. Improve design flexibility
The use of connectors allows engineers to have greater flexibility when designing and integrating new products and when composing systems with components.