date:Aug 15,2019
Return listPcb manufacturer china design connector four key elements
Generally, for pcb manufacturer china,solder does not provide high-quality mechanical support. The soldering strength of the plug-in solder itself is much strongthan that of surface mounting. One is because the plug-in solder has a large cross-sectional area; the other is because the lead is inserted into the through-hole to provide mechanical support.
Usually caused by the connector, there are thermal shock during the initial welding process, temperature cycling during operation, insertion force, twisting force and vibration force.
There are four key elements for pcb manufacturer chinain designing connectors: lead structures, molding compounds, mechanical supports, and lead metal.
(1) Lead structure. The most important feature of the connector leads is their flexibility. Obviously, the flexible lead not only compensates for the coefficient of thermal expansion between the connector and the board, but also cushions the insertion stress. Both gull-wing and J-shaped pins are available. However, because the J-shaped pin structure bends the lead under the component body, such a connection point is difficult to visually measure. Currently, for pcb manufacturer chinaonly a few connectors adopt this structure.
(2) Molding compound. Conventional thermoplastic materials have a lower melting point and are not suitable for surface assembly and reflow technics. High-temperature thermoplastic materials are suitable, but their high melting point increasespcb manufacturer chinatechnicsdifficulty and cost.
(3) Mechanical support. Except in a few cases, the connector should not regard welding as the onlymechanical support, but a variety of auxiliary support methods can be used. The connector can be mounted on the board by riveting, crimping, routing or screwing.
(4) Lead metal. In order to ensure sufficient soldering strength, the plating metal of the connector leads must have high solderability. Poor weldability not only causespcb manufacturer chinaproblems during the production process, but also reduces the weldingstrength. The eutectic Sn-Pb coating provides the highest solderability, while the other coatings are similar.
Currently, a variety of surface assembled connectors are available on the market.
The above is pcb manufacturer china to share the four key elements of smt connector knowledge, if you need more information, please pay attention to our official website:http://www.jbpcba.com