SMT Assembly
Whether your company manufactures electronic devices or telecommunications equipment, chances are that some of your products feature circuit boards with surface mount technology (SMT). While SMT has a number of benefits over traditional through-hole technology (THT), it’s important to understand the limitations of the technique, so you can choose the best type of PCB for your application.
SMT assembly is a high-speed process that relies on automated machinery. This helps to eliminate human errors that can plague a manufacturing line and elevate the risk of poor quality. It’s also a highly flexible technique, allowing for the use of a variety of components and materials.
As such, it’s important to work with an electronics contract manufacturer that offers a wide range of services. A quality firm will help you determine whether or not smt assembly is the right fit for your project and assist with design and prototyping to ensure that the final product meets your specifications.
Staking Pins in SMT Assembly
One of the biggest disadvantages of SMT is that it can be difficult to repair and replace faulty components. This is due to the small size of SMT packages and the lack of a clear solder joint. However, working with a trusted SMT contract manufacturer that uses digitized and connected processes will reduce the likelihood of these issues.
Other disadvantages of SMT include the inability to use fine-pitch components and higher production costs. While these drawbacks are significant, working with a trusted electronics contract manufacturer that offers a complete suite of SMT and THT assembly services can help you mitigate them.
Staking pins are a popular choice for SMT assemblies because they create a strong physical connection to the board. This helps to prevent the pin from moving during handling and shipping, which can compromise signal integrity and cause the device to fail. This is especially important for products that require precise positioning.
In order to stake the pin, it is fitted into a hole on the circuit board. The mounting portion of the pin is placed loosely in the hole, while the collapsible flange or knuckle portions are seated against the circuit board to locate it in the hole. A staking tool is then applied to the lower surface of the pin, with the lower staking surface 72 engaging the collapsed knuckles. The force exerted by the staking tool causes the legs to flatten against each other, forming a strong staked connection to the circuit board.
Once the pin is staked to the board, a molten solder is applied to the lower surface of the pin. The molten solder flows into the interior of the mounting portion and wicks up through the solder flow windows 22 between adjacent collapsed knuckles. The wicking action of the molten solder stiffens the pin, which would otherwise be too weak to hold the components it holds.
The tight staked connection between the petals and the printed circuit board ensures that the pin is held in place prior to heating and reflow soldering. This is particularly important since the pin may be subject to torque during wire wrapping about the knuckle portions.
