Electronic connectorThe basic performance can be divided into three categories: mechanical performance, electrical performance and environmental performance. Another important mechanical property is the mechanical life of electronic connectors. Mechanical life is actually a durability index, which is called mechanical operation in the national standard GB5095. With one insertion and removal as a cycle, it is judged whether the plug-in can normally complete its connection function (such as contact resistance value) after the specified insertion period.

1. In terms of connection function, pull-out force is an important mechanical property. Insertion and extraction force is divided into insertion force and extraction force (extraction force is also called separation force), the requirements of the two are different. The relevant standards stipulate the maximum insertion force and minimum separation force. From the perspective of use, the insertion force is small (hence the low insertion force LIF and the non-insertion force ZIF structure). If the separation force is too small, it will affect the reliability of contact Sex. The insertion force and mechanical life of the connector are related to the structure of the contact (positive pressure), the coating quality of the contact (coefficient of sliding friction) and the dimensional accuracy (alignment) of the contact arrangement.

2. The main electrical properties of electronic connectors include contact resistance, insulation resistance and electrical strength.

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

(2) Insulation resistance is an index to measure the insulation performance between electrical connector contacts and between contacts and shell. Its size is between hundreds and thousands of megaohms.

(3) Resistance, or withstand voltage or medium withstand voltage, refers to the ability to withstand the rated test voltage between the contacts of the connector or between the contacts and the shell.

(4) Other electrical properties. EMI leakage attenuation is an important means to evaluate the shielding effect of connectors. EMI leakage attenuation is an important means to evaluate the shielding effect of connectors. It is usually tested in the frequency range of 100 MHz to 10 GHz. RF coaxial connectors also have electrical indicators such as characteristic impedance, insertion loss, reflection coefficient, and voltage standing wave ratio. With the development of digital technology, in order to connect and transmit high-speed digital pulse signals, a new type of connector, namely the high-speed signal connector, has appeared. Therefore, in terms of electrical performance, in addition to characteristic impedance, there are also some new electrical indicators, such as crosstalk, transmission delay, and time lag.

3. Common environmental properties of electronic connectors include temperature resistance, humidity resistance, salt spray resistance, vibration resistance and impact resistance.

(1) The current maximum working temperature of connectors is 200 (-65 C), except for a few high-temperature dedicated connectors. When the connector is working, the current generates heat at the contact point, causing the temperature to rise. Therefore, it is generally believed that the working temperature should be equal to the sum of the ambient temperature and the temperature rise of the contact point. In some specifications, the maximum allowable temperature rise of the connector under the rated operating current is clearly specified.

(2) The intrusion of moisture resistance will affect the insulation performance of the connection H and corrode metal parts. Constant temperature and humidity test conditions are 90%-95% (according to product specifications, up to 98%), temperature +40+20°C, and test time is at least 96 hours according to product specifications. The humidity and heat alternate test is more stringent.

(3) When the salt spray resistant connector works in an environment containing moisture and salt, the metal structure and the surface treatment layer of the contact piece will produce electrochemical corrosion, which will affect the physical and electrical performance of the connector. In order to evaluate the ability of electrical connectors to withstand this environment, a salt spray test is specified. Hang the connector in a temperature-controlled test box, and spray compressed air with a sodium chloride solution of a specified concentration to form a salt mist atmosphere. The exposure time is stipulated by the product specification and is at least 48 hours.