Fabricating and assembling circuit boards can be a complex and expensive affair. And as a new customer in the PCB industry, you might get confused with how board manufacturers price different products. So it is vital to do PCB cost estimation to help you plan and budget for your electronics project. We will look at these cost estimation factors and ways to approximate board costs accurately. Let's get started!
PCB Cost Estimation Factors
The cost of producing circuit boards falls into four categories.
Pre-Production Inspection and Review
Each PCB fab house offers varying service levels in pre-production inspection, engineering & design review, and DFM review. These levels attract different costs, with the most thorough inspection and review process being the most expensive.
But PCB designs must undergo some basic inspection and review before you get a quote to ensure it is manufacturable. So your project might receive a "no-bid" marking until you rectify errors like clearances.
An engineer checking a PCB design using CAD software
It is vital to note that a design might not trigger a DFM violation when considering the fabrication ability. However, it might create an assembly defect or product failure, for instance, if pads are too close to each other with insufficient solder mask definition.
An affordable basic-level inspection might fail to identify this issue, but expensive advanced-level checking will flag the issue.
What About Design?
We will not include the design time cost because this is your task as a board designer. So if you are not a PCB designer, this design time will be an additional cost. And the longer it takes, the higher the price.
A circuit board design
Keep in mind complex boards take longer to design and require thorough pre-production inspection & review, which will push the circuit board cost higher. However, the cost might be negligible with a high board quantity.
PCB Manufacturing Process Cost Drivers
The crucial factors that drive the manufacturing costs once the design goes into the fabrication phase include the following.
Shorter lead times lead to higher costs because the fab house will have to take extra measures to ensure the project's success. For instance, they might have to source your board materials immediately, halt other production processes to focus on yours, allocate extra man and machine power to your project, etc.
But longer lead times are more forgiving to the pocket because they give fab houses the ability to allocate resources more efficiently. So be prepared to pay more if you want quick-turn PCBs.
Number of Boards
Although manufacturing more boards raises the total project cost, it reduces the price per board. Panelization helps reduce the cost by manufacturing several boards per panel as a single array, which goes through the assembly line efficiently.
Board Size, Materials, Layers, and Number of Sides
Large boards require more dielectric and conducting materials, plus more components. And they might need different materials, such as copper foil, polyimide, or fiberglass. FR4 is the most typical and cheapest material, but polyimide and Rogers are expensive.
Multiple PCBs after production
Alternatively, you can design multilayer and double-sided boards to create compact circuits, but manufacturers will still require more materials to build the additional layers, leading to a higher cost. Also, double-sided boards are more complex and expensive to make but enable you to make compact circuits with multiple components.
HASL and tin-lead are some of the cheapest plating processes but do not provide the best corrosion resistance. Gold and silver finishes give the best surface protection but can increase the cost per board by up to 10%.
A PCB with gold-coated edge connectors
Number and Size of Via Hole
Tiny via holes less than 0.012 mils need advanced laser drilling techniques that might require an adjustment in the manufacturing processes. These holes can increase project costs by 10%-20%. And the more the number of holes, the higher the price increase.
A circuit board with multiple vias
PCB Cost Estimator: Filling Vias
Manufacturers don't fill vias to the top, but some projects require complete filling. Such cases require specialized conductive or non-conductive materials that can add at least an extra 10% to the project's cost.
PCB Cost Estimator: Mechanical Holes
Cost varies depending on the hole shape, size, and plating.
PCB Cost Estimator: Conductor Size and Spacing
Like vias, smaller conductor sizes and spacings are more complex to achieve. So they increase the overall project cost.
PCB Cost Estimator: Add Ons
Some boards require special features due to their application areas. These include complex routing, countersinks, controlled depth drilling, and counter bores. These extra features require additional manufacturing processes and cutting-edge tooling that adds 5-10% to the overall fabrication cost.
PCB Assembly Process Cost Drivers
If you want the bare boards, there will be zero assembly expenses. But these cost drivers will affect the product price if you require assembled boards.
Number and Type of Components
Ordering components in bulk reduces the cost per piece. But if your boards need unique parts, the price will be high. On top of that, an all-SMD assembly can increase the cost by 50% more compared to a through-hole setup.
Electronics factory workers assembling PCBs
Single vs. Double-Sided Assembly
Not only do they require more components, but double-sided boards also have higher assembly costs because the PCBs have to go through the assembly line twice. Plus, they incur higher NRE costs through the process.
SMD Components Lead Pitch
Most manufacturers don't increase the cost due to SMD lead pitch if your board has an all-SMD assembly. But you'll pay extra if it has a mix of SMD and thru-hole components.
Single/double-sided BGA components can increase the cost by 20% compared to other SMT assemblies.
A ball grid array on a PCB
IPC Class (Inspection Charges)
Production and assembly to match IPC-A-600 class 3 standards will be costlier due to the extra inspections required to ensure the processes comply with the required specifications.
ITAR compliance increases assembly costs due to the strict PCB integrity, data integrity, and shipping requirements.
Inspection, Testing, and Qualification
These activities are necessary after assembly to ensure the board does not have defects. The cost depends on the level of inspection & testing and the required qualification standards.
How To Estimate Circuit Board's Manufacturing and Assembling Costs
Considering the factors above, there are two ways to get the estimated cost of building your PCB.
PCB Cost Calculator
Most PCB manufacturers embed PCB cost calculators in their websites to enable potential customers to calculate and estimate the production of a circuit board. But since the fabrication and assembly processes are complex, combining all the factors into one program is challenging.
So you might get a PCB assembly cost calculator, a flex PCB cost calculator, and a PCB design cost calculator as different programs.
Consult a Reputable PCB Manufacturer
Although calculators are quick and enable you to do the math considering all factors, they might not be as accurate. So it is better to contact a reputable PCB manufacturer to get a more precise cost breakdown. At OurPCB, we provide free quotes for PCB designs to help reduce costs for our customers. And we have the required expertise, equipment, and experience to build high-quality circuit boards for your project.
As you can see, you need to consider several factors to determine the cost of producing, assembling, and testing a circuit board. While it is possible to input these variables into a cost calculator, the most accurate method is to consult a reputable PCB manufacturer and assembler like OurPCB. So contact us today with your designs and specify your needs to get a free quote. We'll be in touch.