PCB assembly is a crucial aspect of PCB manufacturing. It is a process that involves several steps. Any defect or error in PCB assembly can cause a further problem. Therefore, these steps must be carefully carried out by professionals.
Engineers need to estimate the PCB assembly cost before working on an electronic project. There are several factors that contribute to the cost of a PCB assembly. Also, the type of project you are designing plays a significant role here. So, how much does a PCB assembly cost? This article provides answers to this question.
Types of PCB Assembly Machine
PCB assembly is a process that involves the use of labor and machinery. Different kinds of machines are used for assembling components on PCB surfaces. These machines include:
Solder paste printing machine
This is an automated machine that applies solder paste to the PCB surface. Solder paste is a combination of metal alloys. It is like glue that keeps your board firm. The components on a PCB will not stay firmly without solder paste. Before applying this paste, the manufacturer places a stencil over the PCB. The stencil has laser-cut holes to help apply solder paste to the board.
Pick and place machine
The pick and place machine is very important in PCB assembly. This machine picks and places components on a bare PCB board. Traditionally, manufacturers use a pair of tweezers to place these components. However, this process is no longer done manually as technology has advanced.
Today’s PCB manufacturers use pick and place machines to accomplish this task. This machine picks SMT components and accurately places them at the appropriate positions. It can place over 30,000 components in one hour. It is very amusing to watch this machine do its job.
Wave soldering machine
Normally, PCBs need to pass over molten solder to get components soldered. In the wave soldering process, the manufacturer applies a flux layer to clean the component pads and contacts. After applying the flux, the machine preheats the board to avoid any form of thermal shock. The circuit board will then pass over a tank of molten solder.
Reflow soldering machine
The reflow soldering machine is commonly used in the PCB industry. The populated PCB moves through a reflow soldering machine. This board moves through different zones at controlled temperatures.
How much does PCB Assembly Machine Cost?
PCB assembly involves the use of several machines. The cost of these machines varies. PCB assembly machines are very expensive. The cost of these machines depends on the function they offer. For instance, the price range of an SMT machine may be between $55,000 and $85,000.
There are several factors that determine the cost of this machine. The type of brand you opt for will also determine the price of a PCBA machine. When getting a PCB assembly machine, ensure you check out for the best supplier. Some companies will deliver the machine and help with installation.
The features offered by a machine will also determine its price. For example, reflow soldering machines can offer different features. The length and the belt width differ from machine to machine.
PCB Assembly Cost
PCB assembly cost is the aggregate amount of money estimated for assembling a circuit board. The cost of PCB assembly may vary based on several factors. PCB assembly cost estimates the amount of money to be spent on labor and materials for a PCB assembly. The quality of a circuit board will influence its performance. Sometimes, cost helps to determine the quality of a board. PCB assembly cost will vary between companies.
For instance, a PCB assembler may charge a sum of $10 for every square inch while another may charge $5 per square inch. The PCB assembly cost depends on a lot of factors. Assemblers have to put a lot in place for PCB assembly. Also, these things are responsible for the cost of PCB assembly
Factors that Determine PCB Assembly Cost
PCB Material type
The type of material you intend to use will affect the cost of PCB Assembly. PCB materials are available in different types and sizes. FR-4 is the commonest material used for manufacturing PCB.
Polyimide is another material used for PCB. It is mostly used for flexible boards that need to be resistant to warping. Other materials used for fabricating PCBs include RF-35 and CEM-1.
Size of board holes
Every part or detail of a circuit board influences the overall cost of production. The number of holes in a PCB isn’t an exemption. PCBs with more holes are more complex to manufacture. Therefore, this increases the cost of assembly. The size of the holes is also a factor. Thinner holes require automated machinery.
For instance, a PCB with 0.33mm holes and below 0.2mm holes will have different drilling costs. This is because the circuit board has two specifications of the hole. If the holes are 0.1mm, the assembler will have to use laser drilling. This is more costly than Mechanical drilling.
Copper thickness
PCBs have varying copper thicknesses. The application requirements will determine the thickness of the copper in the PCB. The higher the copper thickness, the more costly the board. For instance, a 10 Oz PCB will be more expensive than a 5 Oz PCB. PCBs with higher copper thickness are very complex to fabricate.
Labor costs
PCB assembly cost also depends on the costs of labor. The assembly of PCB requires skilled personnel that can handle electric equipment and automated machinery.
The location of the PCB assembly company will determine the cost of labor. Some countries don’t have skilled labor. In countries like China and the USA, there are more skilled PCB assemblers. China is one of the cheapest and best places to set up a PCB assembly company.
Mounting technology
The type of mounting technology employed will determine PCB assembly cost. Surface Mount Technology and Through-Hole Technology are the two common mounting techniques. PCBs with SMT components are cheaper than that of THT. If a circuit board needs ball grid arrays, the PCB cost will be higher. Also, THT is very complex as holes have to be drilled into the circuit board.
Number of PCB layers
PCBs feature a different number of layers. These layers affect the cost of PCB assembly. PCBs with more layers are more expensive to fabricate. Most times, high-performance PCBs are multilayer boards. Multilayer boards require more materials for their fabrication.
PCB surface finish
The cost of surface finish will also be included in the PCB assembly cost. The application requirements will determine the type of PCB finish you need. For some companies, the type of surface finish isn’t a major factor in PCB assembly cost. The surface finish types include:
- HASL finish (Hot Air Solder Leveling)
- ENIG finish (Electroless Nickel Immersion Gold)
- OSP finish (Organic Solderability Preservative)
- IAG finish (Immersion Silver)
- ISN finish (Immersion Finish)
Design Complexity
You can reduce the complexity of your layout. For example, assemblers can assemble all parts on the same side of the PCB to reduce cost. Therefore, you won’t need to pay too much. Some designs such as ball grid arrays and conformal coating can increase PCBA cost.
How to Calculate PCB Assembly Cost
The cost of a PCB manufacturing and assembly requires calculating the sum of some parameters.
PCB assembly cost is the sum of PCB board cost, SMT/DIP soldering cost, component procurement cost, PCBA test cost, special packaging, and logistics cost.
PCB board cost
This refers to the amount of the bare PCB board. For a PCB assembly, a bare PCB board is important. The assembler mounts the electronic components on the bare board.
Component procurement cost
This refers to the cost of procuring the components on the bare board. The PCB assembly company buys the components based on the BOM provided.
SMT/DIP soldering cost
The cost of solder pads is also included when calculating PCB assembly cost. The price of SMT depends on the number of solder pads. The more the number of solder pads, the higher the price.
PCBA test cost
The PCB Assembly cost will also include the cost of inspection and testing. Testing and inspection are important aspects of PCB assembly. If customers require for additional PCBA function test, the assembler will charge an extra fee.
Stencil cost
This is another cost that helps you determine the PCB assembly cost. A stencil is a crucial tool in PCB assembly.
How to Reduce the PCB Assembly Cost
You can reduce the cost of a PCB assembly by following these rules:
Optimize the schematic design of PCB boards
You can optimize the schematic design of the circuit board to reduce PCBA costs.
- Use SMT parts
With SMT parts, you can place more components on the circuit board. Also, SMT assembly is less expensive than THT assembly.
- Less drilling
Drilling holes on a PCB board consumes a lot of time. When there are more holes to drill on a board, there is more cost. Therefore, fewer holes can help you save more money.
- Use the standard PCB size
Smaller boards require a lower board price. Opting for the standard size of a circuit board can minimize the cost.
- Reduce the number of layers
Boards with more layers require more cost of production. One of the best ways to reduce the cost of PCB assembly is by reducing the number of layers.
- Through hole
Blind holes are costlier than through-hole. Through-hole is a better option. It reduces the cost of PCB assembly.
Adjust Lead time and order volume
You can adjust the volume of your order and lead time to reduce PCBA costs. High order volume reduces the cost for each PCB assembly. You can also reduce the lead time. When you request for quick lead time, you are likely to pay more. However, it is important you know how to calculate the lead time. Different PCB assemblers calculate their lead time in different ways.
Prepare a complete and effective BOM
BOM, the bill of materials is an important document in PCB assembly. This document contains the list of items, components, and raw materials for fabricating a PCB. A comprehensive BOM would feature:
- Part number
- Quantity
- SMT method
- Manufacturer name
- Case/package type
- Reference designator
Most times, PCB assemblers have guidelines for creating BOM. You can easily fill this template to speed up the quotation procedure. It is important you include components replacement in a BOM. This is because components may upgrade rapidly as electronics advance.
Locate an effective and low-cost PCB assembler
This is one of the best ways to reduce the cost of PCB assemblers. There are reliable assemblers who offer low-cost services. However, it is important you make an inquiry about the assembler. You can do this online. Ask questions and check reviews. Also, it is important to check the certifications of the PCB assembler.
Factors to Consider When Choosing a PCB Assembler
There are several PCB assembly companies across the world. PCB users might have to deal with getting the best PCB assembly company. It is important you check out certain factors when choosing a PCB assembler. These factors include their specialization and the quality they deliver. Below are factors to look out for when choosing a PCB assembler:
Quality
You should consider the quality the PCB assembly company is ready to offer. The best PCB assembly company will provide you with quality boards. This company won’t compromise quality for anything. You can make an inquiry about this by checking the reviews of their customers.
Experience
This is another factor you need to take into consideration. You should opt for a company that has gathered a lot of experience in PCB assembly. You need a PCB assembler that specializes in the type of PCB board you want.
Cost
The cost of PCB assembly depends on some factors. However, your budget will determine the PCB assembly company to opt for. It is crucial you opt for a company that meets your budget and technology demands.
Turnaround time
This is the time it takes for assemblers to deliver your products. Some companies assemble PCBs within a short time. However, when assemblers deliver PCBs quickly, they are likely to charge more fees. An assembler might need to put other things on hold to deliver on time.
Certifications
This factor is very important when choosing a PCB assembly company. Check out for companies with standard certifications. This helps you to know how reliable and effective the PCB assembly company is.
Why PCB Assembly Cost Matters
It can be quite tempting to opt for a cheap PCB assembly. PCB users working with a tight budget for their project might consider a cheap option. However, it is crucial to take note that the cost of PCB assembly can vary. Also, the cost of a PCB assembly may determine some things. The quality of your circuit board will affect the performance of your product.
Also, PCB assembly cost talks about a lot of things. It determines the performance, reliability, and functionality. Ensure you discuss the pricing of your PCB with your assembler. This is very important; especially when it has been a while you ordered anything.
If your PCB assembly cost varies greatly from that of others, ensure you make inquiry. The variability might indicate poor functionality and quality. Although different companies may charge differently, this shows the variation in different companies. For example, an assembler may charge $10 for a square inch. Another company may charge $2 for a square inch.
The cost of PCB assembly helps to determine a lot of things. Sometimes, PCB users need to compare this cost with their budget. Since PCB assembly is a complex process, it requires more cost.
Frequently Asked Questions
Why are Circuit Boards Expensive?
Circuit boards are expensive because their production requires some components, raw materials, and skilled labor. These factors contribute to the high price of circuit boards. Also, the requirements of some applications contribute to the high cost of PCBs.
What is the price range of a PCB?
The price of a PCB can be as low as $10 and as high as $500. However, the production cost of a PCB depends on the manufacturer. Some other factors could also contribute to the price.
Conclusion
The cost of PCB assembly varies between companies. However, there are certain factors that contribute to this variation. PCB assembly is a core aspect of PCB manufacturing. It is a process that requires several steps. It is important to have quality in mind when assembling a PCB. Also, your PCB assembly cost determines a lot about your PCB.
