When
PCB board replaced the slow and cumbersome manual wiring boards and systems of the past, it became a novel technology that allowed electronics engineers to assemble complex electronic systems relatively quickly, easily and inexpensively. As a result, the electronics industry has put great effort into making these boards as easy to manufacture as possible. Significant capital has been invested and used in design software to assist in the design, manufacture, assembly, inspection and testing of printed circuit boards. These technologies allow design engineers in the electronics business to invest in improved processes that reduce part size, produce surface mount (SM) and ball grid array (BGA) packages, reduce PCB line width and size. Other features, better card inspection with an X-ray imager, etc. The slow introduction of artificial intelligence (AI) into design software means that some critical work, such as the placement of PCB board components, is still manually controlled by layout engineers. As a design engineer, you will need to ensure an understanding of part placement to ensure design stability.
The evolution of component placement throughout your design career
I designed a low density, flexible circuit board using the wire wrap method. Then came the opportunity to make printed circuit boards. I started with simple PCB boards (through hole parts, reasonably sparse design) to simple and even large SMT parts. This means that the manual soldering process that follows the PCB board design process is also fairly simple early on. However, as you go further in your career, you are assigned to use high-density PCB boards for fabrication with tiny SMT, BGA, and QFN parts in fragile design environments, with fine wires and components in layouts small spacing between. This makes "assembling" a PCB board a new variable that design engineers must contend with. For some, this might be an unpleasant surprise, but I believe be forewarned.
Place the parts on the PCB
A PCB board can be assembled in one of many different ways. Design engineers should consider specific assembly techniques, such as machine assembly, manual assembly, hybrid assembly (manual and infrared oven), etc., before embarking on designing a PCB board. These options often depend on cost, time, volume, and the type of design the engineer is considering. Many considerations drive the process of placing parts on a PCB board. Signal length (small and ), ease of assembly, and ease of testing are all critical to assembling a PCB board. Below, we'll explore the unique components of each aspect of assembly.
Conference Types and DFA Important Guidelines
Throughout the electronics industry, you will almost certainly be dealing with many different kinds of assembly. It's important to educate yourself about what each process involves, the benefits and typical uses of each form of assembly, and how best to optimize the DFA process to coincide with the production of the final PCB board.
PCB board component placement in machine assembly
Machines can often be used to assemble and use them for mass production. The component footprint on the PCB board must be, and must follow all design rules. Machine assembly does not provide any flexibility that can be obtained by using humans in the loop to fabricate the PCB. Machine-assembled cards are yes. It uses expensive industrial machines to design and complete the assembly of the PCB board according to the rules. The need for non-re-engineering time means this method is usually reserved for high volume welding.
Manual assembly and solder bridge issues
Manual assembly is a slow technique. This is time-consuming and requires full-time human work. It's also error-prone. Short circuits caused by solder bridges have ruined the careers of many engineers. As a result, most agencies work with two technicians - an assembler and a quality assurance (QA) technician, who check the assembler's work to make sure the solder bridges on the PCB don't grow up. The assembly technician must be a very talented person. They make you break design rules that machines and even hybrid assemblers don't allow. Therefore, if a design (generally a low-volume design) violates design rules to achieve compactness, hand soldering is the way to go.
Infrared oven or wave soldering in hybrid assemblies
The rest of the market is dominated by hybrid assembly methods, in which technicians place components on cards and use an IR oven or wave soldering machine to complete the soldering process. Hybrid components typically use stencils and solder paste to create solder-coated PCB boards, where assembly technicians simply place parts on designated footprints and place the filled cards in an oven to complete the reflow/soldering process. If errors such as vertical lift occur during oven soldering, the hybrid assembler must leave enough space between the parts to place them by hand and rework the solder card. QA technicians may also be part of the line.
Component Placement in High Density PCB Board Design
The need to manufacture high-density PCB boards has created new temptations that do not arise in sparse designs. When engaging in high-density design activities, don't forget that even in high-density systems, old design methods must be followed. One of the common practices that designers refuse to follow is to discard reference code, which can lead to a significant increase in density. However, the assembler still needs this information to assemble the card. Removing these indicators means that engineers are now responsible for creating additional documentation to assist and guide assembly technicians during the process of assembling PCB boards. Remember – PCB boards, such as schematics or programs, can take a lot of human effort to go through the development process before they become reality, so each step must include enough documentation to allow others to work with your creation interact. Always consider how your design choices will be viewed by people who interact with your design after you. We all believe that the next person who probably won't pay dearly for your gadget. Someone on the design and assembly team may have to convert your
PCB board into a fully operational electronic system to make your dream a reality.
