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

1. Mechanical performance In terms of connection function, the insertion force is an important mechanical property. Insertion force is divided into the insertion force and pull out force (pull force also known as separation force), the two requirements are different. The maximum insertion force and the minimum separation force in the relevant standard, which indicates that the insertion force is small from the point of view of use (thus having a low insertion force LIF and a non-insertion force ZIF structure) and the separation force is too small, It will affect the reliability of contact.

Another important mechanical property is the mechanical life of the USB connector. Mechanical life is actually a durability (durability) indicators, in the national standard GB5095 it is called mechanical operation. It is a single insert and a pull out as a cycle to the provisions of the plug-in cycle after the USB connector can normally complete its connection function (such as contact resistance) as a basis for judging.

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

2. Electrical performance The main electrical properties of the USB connector include contact resistance, insulation resistance and electrical strength.

① contact resistance high-quality electrical USB connector should have a low and stable contact resistance. The contact resistance of the USB connector ranges from a few milliohms to several tens of milliohms.

(2) Insulation resistance measures the insulation performance between the USB connector contacts and between the contacts and the enclosure, which is of the order of several hundred megohms to several gigahertz.

③ Dielectric strength or resistance to voltage, dielectric pressure, is to characterize the USB connector contacts or between the contact between the shell and the ability to withstand the rated test voltage.

④ other electrical performance.

3. Environmental performance Common environmental performance including temperature, moisture, salt spray resistance, vibration and shock.

① temperature The current USB connector, the maximum operating temperature of 200 ℃ (a few high-temperature special USB connector except), the minimum temperature of -65 ℃. As the USB connector works, the current at the contact point to generate heat, resulting in temperature rise, it is generally believed that the operating temperature should be equal to the ambient temperature and contact temperature rise and. In some specifications, the maximum permissible temperature rise of the USB connector at rated operating current is specified.

② moisture resistant moisture intrusion will affect the connection h insulation properties, and corrosion of metal parts. Constant humidity test conditions for the relative humidity of 90% to 95% (according to product specifications, up to 98%), temperature +40 ± 20 ℃, test time by product, at least 96 hours. Alternating hot and humid test is more stringent.

③ salt-resistant USB connector in the environment containing moisture and salt work, the metal structure, the contact surface treatment layer may produce electrochemical corrosion, affecting the physical and electrical properties of USB connectors. In order to evaluate the ability of the electrical USB connector to withstand this environment, a salt spray test was specified. It is the USB connector hanging in the temperature controlled test chamber, with the specified concentration of sodium chloride solution with compressed air spray, the formation of salt mist atmosphere, the exposure time by product specifications, at least 48 hours.

④ Vibration and Shock Resistance to vibration and shock is an important feature of the electrical USB connector. It is particularly important in special applications such as aerospace and aerospace, railways and road transport. It is a test of the robustness and electrical power of electrical connectors. Important indicators of contact reliability. In the relevant test methods are clearly defined. The peak acceleration, duration, and impulse pulse waveforms, as well as the duration of electrical continuity, shall be specified in the impact test. 1. Mechanical performance In terms of connection function, the insertion force is an important mechanical property. Insertion force is divided into the insertion force and pull out force (pull force also known as separation force), the two requirements are different. The maximum insertion force and the minimum separation force in the relevant standard, which indicates that the insertion force is small from the point of view of use (thus having a low insertion force LIF and a non-insertion force ZIF structure) and the separation force is too small, It will affect the reliability of contact.

Another important mechanical property is the mechanical life of the USB connector. Mechanical life is actually a durability (durability) indicators, in the national standard GB5095 it is called mechanical operation. It is a single insert and a pull out as a cycle to the provisions of the plug-in cycle after the USB connector can normally complete its connection function (such as contact resistance) as a basis for judging.

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