The basic performance and characteristics of the connector

The basic performance of connectors can be divided into three categories: mechanical performance, electrical performance and environmental performance.

1. Mechanical properties From the connection function, the insertion force is an important mechanical property. Insertion force is divided into insertion force and extraction force (extraction force is also called separation force), and the requirements of the two are different. There are regulations on insertion force and separation force in the relevant standards, which shows that from the perspective of use, the insertion force should be small (thereby there are structures with low insertion force LIF and no insertion force ZIF), and if the separation force is too small, it will affect the reliability of the contact.

Another important mechanical property is the mechanical life of the connector. Mechanical life is actually a durability index, which is called mechanical operation in the national standard GB5095. It takes one insertion and one extraction as a cycle, and judges whether the connector can normally complete its connection function (such as contact resistance value) after the specified insertion and extraction cycle.

The insertion force and mechanical life of the connector are related to the contact structure (positive pressure), the coating quality of the contact part (sliding friction coefficient) and the dimensional accuracy (alignment) of the contact arrangement.

2. Electrical performance

2. Electrical properties mainly include contact resistance, insulation resistance, current and electric strength

① Contact resistance: High-quality electrical connectors should have low and stable contact resistance. The contact resistance of the connector varies from a few milliohms to tens of milliohms.

② Insulation resistance: It is an index to measure the insulation performance between the contacts of the electrical connector and between the contacts and the shell, and its order of magnitude ranges from hundreds of megohms to thousands of megohms.

③ Dielectric strength or withstand voltage: characterizes the ability of the connector contacts to withstand the rated test voltage between the contacts and the housing, depending on the gap between the circuits (that is, the distance between the contacts and the creepage distance) and The insulating material used in connectors.

④ Current: limited by the electrical connector and the wires it terminates.

Other electrical properties and electromagnetic interference leakage attenuation are used to evaluate the electromagnetic interference shielding effect of the connector, and are generally tested in the frequency range of 100MHz~10GHz.

For RF coaxial connectors, there are also 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, that is, a high-speed signal connector, has emerged. Correspondingly, in terms of electrical performance, in addition to characteristic impedance, some new electrical indicators have also appeared. , such as crosstalk (crosstalk), transmission delay (delay), time lag (skew), etc.

3. Environmental performance

Common environmental properties include temperature resistance, humidity resistance, salt spray corrosion resistance, etc.