The life of the pin header and female connector is directly linked to its electrical performance, and the performance of the pin header and female connector can only be optimized by relying on the plating layer, so the quality of the plating directly determines the connector.
That is, the control of the existing and about-to-form thin films on the surface of the contact coating.
One of the main requirements for the electrical performance of pin headers is to establish and maintain a stable pin header impedance. To achieve this, a metal contact interface is required to provide such inherent stability. Establishing such a contact interface requires that the surface film be able to avoid or split during contact mating. These two different options define the difference between precious or rare metals and ordinary metals.
- To varying degrees, precious metal coatings (such as gold, palladium and their alloys) are essentially free from the surface film.
Interfacial metal contact is relatively simple for these coatings, since it only requires movement of the companion of the contact surface during mating. Usually this is easy to achieve. In order to maintain the stability of the contact interface impedance, the design of pin header and female header should pay attention to maintaining the noble metal property of the contact surface to prevent the influence of external factors such as contamination, diffusion of substrate metal and contact wear.
- Ordinary metal coatings, especially tin or tin alloys, are naturally covered with an oxide film.
The role of the tin contact coating is that this layer of oxide is easily destroyed during mating, so that the metal contact is easily established. The requirement of pin header and female header design is to ensure that the oxide film is broken when the pin header and female header are matched, and that the contact interface is no longer oxidized during the validity period of the electrical connection retainer. In wear corrosion, it is the main performance degradation mechanism of tin contact coating. The pin header mother silver contact coating is best treated as a normal metal coating, since the coating is susceptible to corrosion by sulfides and chlorides. Nickel plating is also usually regarded as a common metal due to the formation of the valve through.