The Printed circuit board is assembly refers to the process of attaching various electronic components to a printed circuit board to develop and complete a fully functional printed circuit assembly. Basically, there are different types of PCB assembly utilized in this process, one is the surface-mount construction, and the other is the through-hole construction. Both of these methods have different benefits when put to use, and the surface mount technique needn’t take up much space. Nonetheless, both these methods have their own advantages and disadvantages in the integral process of assembly. So, what are the cost included in the PCB assembly?
PCBs is used to connect and support various electronic components by using different conductive pathways, methods, tracks and traces. These electronic components are effectively etched from copper onto a non-conductive substrate. What’s more, once the PCB process is completed.then the components will be attached to produce these assemblies, and the component leads will be carefully inserted through the holes in the PCB and the surface-mount construction, and then, the electronic components will be placed on the external pads of the printed circuit board. Lastly, the component leads in both types of this construction will be mechanically fixed to the PCB with the help of soft metal molten solder.
What is the Significance of the PCB Assembly?
These units are essential as they can upgrade the electronic device or gadget without any hassle.
Prototype PCB assembly refers to the process of attaching various electronic components to a PCB and completes a fully functional printed circuit assembly. Basically, there are two types of construction utilized in the process of PCB assembly, they are surface-mount construction and through-hole construction.
Difference Between PCB Assembly And PCB Manufacturing
You may have heard some manufacturers claim that they can “manufacture” printed circuit boards. Other manufacturers claim they can “assemble” circuit boards. So, are they saving the same thing, or is there any difference between printed circuit board manufacturing and printed circuit board assembly?
Actually. there is a difference. Printed circuit board assembly means that a manufacturer will assemble the PCB by soldering the electronic components onto the circuit board itself. Usually, such manufacturers will have a design that they work from.
Manufacturing printed circuit boards is a much more extensive process than circuit board assembly, it requires the manufacturer to design the printed circuit board and create a PCB prototype. And then, the manufacturer will be able to assemble the PCB.
PCB is the circuit board, and PCBA is the circuit board plug-in assembly, added SMT and DIP process.
PCB is a bare board while PCBA is a finished board. It is made of a glass epoxy resin material. According to the number of signal lavers, it is divided into 4, 6 and 8 lavers, and the most common are 4 laver and 6 laver PCBs.
PCBA may be understood as a finished circuit board, and PCBA can only be counted after the assembly on the circuit board is completed.
PCBA=Printed Circuit Board +Assembly.
In other words, the PCB blank board goes through the SMT and then goes through the entire process of the DIP plug-in, abbreviated as PCBA.
Usually, a conductive pattern that provides an electrical connection between components on an insulating substrate is called a printed circuit.
There are no components on the top of the PCB, which is often referred to as the “Printed Wiring Board (PWB).”
PCB assembly type
1. Surface Mount Assembly
• SMT, which doesn’t require drilling, is less mechanically stressful than the thru-hole assembly.
• SMT is a faster and lower-cost manufacturing process than the through-hole assembly.
SMT is the optimal assembly method for component-rich designs and allows for more connections per component than the thru-hole assembly.
• SMT-assembled PCB prototypes and component repair would be more difficult than those on board assembled by through-hole soldering.
• Usually, SMT components do not as high-powered or high-voltage as thru-hole components.
2. Through-Hole Assembly
•Thru-hole soldering provides a stronger mechanical bond than any other technique.
•Thru-hole soldering is the optimal technique for connectors, transformers, electrolytic capacitors, and other circuit board components.
•Thru-hole soldering is considered to be the go-to process over SMIT for many military or aerospace products.
Thru-hole soldering requires drilling into the bare circuit board, which makes it a more time-consuming process than SMT.
Thru-hole soldering is more expensive than using SMT.
Thru-hole mounting may not be allowed as high a component density as SMT does. Thru-hole mounting often requires hand-soldering, which is considered to be less reliable than the reflow ovens used in surface mount PCBA.
3. Mixed technology (SMT and thru-hole soldering together)
In general, this method is used for more complicated boards where some surface mounting combined with some drilling would best suit a unique PCB layout.
Higher cost and longer assembly time than normal due to PTH components.
Printed Circuit Boards Assembly Process
Step 1: Solder Paste Stenciling
The first step of PCB assembly is to apply a solder paste to the board. This process is just like screen-printing a shirt, except instead of a mask, a thin and stainless-steel stencil is placed over the PCB. This enables assemblers to apply solder paste only to certain parts of the would-be PCB. These parts are where components will be placed in the finished PCB.
Step 2: Pick and Place
After applying the solder paste to the PCB board, the PCBA process will moves on to the pick and place machine a robotic device places surface mount components or SMDs on a prepared PCB. SMDs involve most non-connector components on PCBs today. These SMDs are then soldered on to the surface of the board in the next step of the PCBA process.
Step 3: Reflow Soldering
Once the solder paste and surface mount components are all in the place, they need to remain in there. This means the solder paste needs to solidify. adhering components to the board. PCB assembly finishes this through a process called “reflow”. After the picking and placing process concludes, the PCB board would be transferred to a conveyor belt. This conveyor belt would then moves through a large reflow oven, which is somewhat like a commercial pizza oven. This oven is made up of a series of heaters which gradually heat the board to temperatures around 250 degrees Celsius. or 480 degrees Fahrenheit. This is hot enough to melt the solder in the solder paste.
Step 4: Inspection and Quality Control
You know, once the surface mount components are soldered after reflow, the assembled board needs to be tested for functionality. Usually, movement during the reflow process will result in; poor connection quality or a complete lack of a connection. What’s more, shorts are also a common side effect of this movement, as misplaced components can sometimes connect portions of the circuit that should not connect.
Step 5: Through-Hole Component Insertion
Depending on the type of board under PCBA. the board is possible to include a variety of components beyond the usual SMDs. These include plated through-hole components. or PTH components. A plated through-hole is a hole in the PCB that is plated through the board. PCB components use these holes to signal from one side of the board to the other. In this case, soldering paste would not do any good, as the paste will run straight through the hole without a chance to adhere.
Step 6: Final Inspection and Functional Test
After the soldering step of the PCBA process is finished, a final inspection will test the PCB for its functionality. This inspection is known as a “functional test”. The test gets the PCB through its paces, simulating the normal circumstances in which the PCB will operate. And finally, power and simulated signals run through the PCB in this test while testers monitor the PCB’s electrical characteristics.
What Affect PCB Assembly Cost
Every electronic engineer or designer wants to know how do you get the best PCB Assembly quote, and how do you what price will affect PCB assembly cost. Here are some tips to guide you on how to control PCB assembly price. PCB Assembly quote. First, a clear understanding of attributes to the cost of PCB assembly (PCBA). Some of the biggest cost drivers include:
1. Assembly Type
2. Components Placet
3. Total numbers of components (SMD+ DIP)
4. Package Size of components
5. Components Package6) Processes Required
6. Quantity and Batch Size(s)
8. Special Part Preparation Requirements (i.e. lead length, height min/max, spacing)
9. Total Cost of BOM
10. Bare Board (PCB) Layer and Material
13. Assembly Compliance
14. Test Requirements (RayMing prefer to test all PCBA boards before ship. We would like you can show us how to test
16. Delivery ( MOKO Technology provide quick turn PCB assembly services )
All of these 16 tips will affect the PCB assembly price, so you can choose the best one to save the cost, When you source parts, You can provide multiple component sources for each component so you can easily control some cost, not only from Digikey, some agent also have strong price support one someone components.
How to Decrease the PCB Assembly Cost
With improving technologies, the cost of every production is increasing. Profit margins are being raised. When you look for quality products for your application, the costs are likely to be even higher. But, you obviously want to reduce spending on your expenses, without compromising on the quality. Is that even possible?
Electronics companies are always facing issues while attempting to cut down costs as the technology is constantly changing. Electronic devices are always evolving into more and more complex products, in order to meet consumer demands. This is why technology companies are evolving to find new processes for developing products that the end-users demand.
In this blog, you’ll learn about the most common electronic product -the PCB assembly -which is seen as a vital component in almost all kinds of electronics. Even though such a common component, PCB assemblies are very expensive, as the manufacturing process involved to build them is very intricate and complex requiring lots of components and labor. Affording such expensive PCBs may become a problem when there are innumerous PCBs involved in your applications. But, neither can you compromise on the quality to reduce their costs. So then, what are you supposed to do? You must approach a PCB assembly manufacturer from China whose goal is to reduce PCB assembly costs without compromising on quality. One such manufacturer is MOKO Technology.
Here are several tips that PCB assembly manufacturers may use to reduce the costs of PCB layout manufacturing.
- Understanding that size can result in a more efficient panelization of the board. where more board per panel results in a lesser cost per board, they may use square or rectangular shaped boards in a standard 18-inch x 24-inch manufacturing panel.
- They may use standard Fr4 material-% or 1 oz. copper, and 1/16 inch PCB thickness.
- They may aim to use .010 inch or larger holes to keep the costs down, as the size of the holes on the board really makes a difference.
- They may keep the schematic and parts list changes to the minimum to further reduce costs. Quicker turnaround time is more expensive: thus they may allow enough time for a turnaround.
- They include all necessary information regarding the layout guidelines, schematic files, reference layout designs, and mechanical requirements while submitting the files for pricing to minimize the costs.
How does MOKO Technology decrease the PCB assembly cost
MOKO Technology has developed its pricing schedule based on various factors that determine PCB assembly costs. Some of our customers call us to better understand the factors involved assembly pricing In general, the factors that cause pricing differences to include PCB dimensions, part types and quantities.soldering methodology, type of inspections, etc.
MOKO Technology can help you reduce costs with such ideas, and make sure to involve them early in the process so that all kinds of decisions can be taken care of beforehand that can help keep the costs down MOKO Technology offers a variety of services with EMS capabilities of product designing, system architecture. value engineering, manufacturing, logistics along with all kinds of required tests done to provide the best quality PCB assemblies to clients.
MOKO Technology offers lead-free assembly based upon the customer’s specifications. We own two additional production lines dedicated to lead-free assembly. We employ RoHS-compliant, state-of-the-art soldering methods. The lead-free assembly may result in price changes. however. You can obtain the actual costs by contacting one of our sales representatives.
The type and size of the parts that you select will also determine the final PCB assembly cost. Charges may also change if you specify lead-less parts, such as BGA, OFN, etc. In addition, costs may vary with package sizes (e.g.. 0201, 1206, etc.) as well as the inspection methods you specify.
MOKO Technology has a variety of inspection methods, including in-circuit and functional tests, available to ensure high-quality PCBs. We are capable of the following tests: visual inspection for basic quality verifications, x-ray testing for lead-less devices and blank PCBs. Of course, we also have AOI inspections to test solder paste applications, missing components, and polarity. Our inspections are completed without additional charges.