Assembling a printed circuit board requires more than raw components and well-designed boards. It also requires the right technology. In this case, you can choose from multiple options, each of which brings something different. For example, using surface mount technology (SMT) and manual soldering and placement machines. Some PCB assembly processes require only one technique, while others require a combination of two or more. For example, most circuit boards require a combination of through-hole technology (THT) and surface mount technology. Knowing when, where and how to integrate these technologies is an important consideration when choosing a turnkey PCB assembly company to complete your project or production. It is also important to understand that the steps involved in PCB assembly vary for each technology. The FS Tech below summarizes some of the important steps involved and how these techniques differ. PCB Assembly Procedure Solder paste: If you follow the traditional PCB assembly process, the first step is to use solder paste. Note that this does not apply to THT, but SMT must be placed and/or printed.Component Placement: The next step in the traditional PCB assembly process is to place components on the board. This can be done manually or with the help of a machine (system selection and location). In THT assembly, components are placed manually, requiring incredible precision. During SMT, the robot places system components on the board. Note that automatic nesting is faster and more accurate than manual nesting. Reflow Soldering: The next step in the traditional PCB assembly process is reflow soldering, in which the solder first melts and then solidifies. The circuit board and all its components pass through an oven that heats and liquefies and cools the solder, allowing connections to be made before the board enters the heat sink.Note that reflow soldering is not required for the THT process. Instead, the second step is to inspect the board and place the correct components. This is because there is a manual placement process with a visual inspection of the shipping frame designed to help ensure placement accuracy. The SMT process also involves reflow soldering at this point. The board goes into a furnace to melt the solder paste, let it flow if necessary, and then the board goes through a series of heat sinks that gradually lower the temperature, curing the solder on the board and her components sticking it in place. Inspection: The next step in the traditional PCB assembly process is a visual inspection of the board, solder, and components. Note that this step has been performed in both the THT and SMT steps.Through-hole insertion: The traditional process requires manual insertion of through-holes after the reflow and inspection process. Soldering is usually done by hand, but can also be done using wave soldering.Meanwhile, wave coupling occurs during the THT process. The entire board is moved through liquid solder, which is then passed through a heat pipe to harden the solder. Note that there are no steps involved in the SMT process (actually only three steps are performed and summarized, but a visual inspection is required to ensure accuracy and reduce the chance of error). Final Inspection and Cleaning: The final step in the traditional PCB assembly process is final inspection and cleaning of the board, solder joints and components to ensure any residue or excess solder is removed.The right PCB assembly process for youWhile the SMT assembly process is faster and generally more accurate than the traditional PCB assembly process or THT process, it is not the best option. For example, if you only need to assemble a prototype board, the THT method might be a better choice. Every situation is different, and no one solution will always meet all needs. Simply put, FS Tech PCB Assembly is the process of putting everything together and making it work from many components.
