Connectors, as critical interfaces between electronic devices, directly affect the overall operation of electronic systems through their performance parameters. These parameters include not only the connector's physical dimensions and electrical characteristics, but also environmental adaptability, mechanical life, and other aspects. A thorough understanding of these performance parameters allows for a more comprehensive understanding of connector quality and reliability, providing strong support for the design and optimization of electronic systems.
1. Mechanical Parameters
Mating and extraction force is an important mechanical indicator of connector performance, encompassing both insertion and extraction forces. In practical applications, we aim for the lowest possible insertion force to ensure ease of operation, while the extraction force must not be too low to guarantee a stable contact.
Mechanical life, as a measure of durability, is tested by simulating mating and extraction cycles. After a specified number of cycles, the connector must maintain its connection function, such as stable contact resistance, to be considered (qualified). This indicator is closely related to the structure of the contacts, the quality of the plating on the contact areas, and the dimensional accuracy of the contacts.
2. Electrical Parameters
Contact Resistance
High-quality electrical connectors should possess low and stable contact resistance, typically ranging from a few milliohms to tens of milliohms.
Rated Current
This depends on the material and cross-sectional area of the terminals. A larger cross-sectional area results in lower impedance per unit length, less heat generated when current flows, thus ensuring a smaller temperature rise at the terminals and allowing for safe conduction of larger currents.
Insulation Strength
This reflects the insulation performance between the internal contacts of the connector and between the contacts and the shell. Its value typically ranges from hundreds of megohms to thousands of megohms.
Dielectric Strength or Withstand Voltage
Also known as dielectric withstand voltage, this measures the connector's ability to withstand the resistance between its contacts or between the contacts and the shell at the rated test voltage.
Other Electrical Parameters
Electromagnetic interference leakage attenuation measures the connector's shielding effectiveness against electromagnetic interference in the 100MHz to 10GHz frequency range. In addition, RF coaxial connectors also involve electrical indicators such as characteristic impedance, insertion loss, reflection coefficient, and voltage standing wave ratio.
3. Environmental Adaptability
Connectors must maintain stable performance in various environments. Regarding temperature range, the highest operating temperature for current connectors can reach 200℃, while the lowest temperature can withstand is -65℃. In addition, temperature resistance tests and temperature cycling tests are required to ensure stability under different temperature conditions.
Meanwhile, connectors must also withstand environmental challenges such as moisture and salt spray. Moisture intrusion can affect their insulation performance and cause metal parts to rust. Therefore, constant humidity and alternating humidity tests are essential. Salt spray tests and corrosive gas tests (such as SO2 and H2S) are used to verify the connector's corrosion resistance in environments containing moisture and salt.
Furthermore, vibration and shock resistance are also important performance indicators for connectors. In specialized applications such as aerospace and railway, these properties are particularly critical. Vibration tests and physical shock tests can verify the robustness of the connector's mechanical structure and the reliability of its electrical contacts.