As with most things you can purchase, there’s a strenuous relationship between cost and quality when it comes to PCB assemblies. However, there is a happy medium to be found between the two, and these tips can help reduce PCB assembly cost without sacrificing quality.
The First Step to Reducing PCB Assembly Cost: Optimize your Bare Board Schematic
Reducing cost is possible from the very first step in the process. Your bare PCB design can be optimized to prevent errors and reduce cost. You can subject your PCB’s to a design-for-manufacturing (DFM) test, offered free of charge by some manufacturers, to discover possible areas of concern.
If you are designing your board in-house, free software like Eagle is available to produce your schematic. You can read about some of its benefits and comparisons to similar software here.
Areas where the bare board can be optimized for efficiency and price include:
- Layer Count
This one is obvious, but the more layers in your assembly, the higher the cost. You’ll also want to ask for clearances between board layers to avoid higher reject rates.
- Size and Shape
The larger the board, the more expensive it will be. Shape can be a key factor as well. Keeping your board to common square and rectangle shapes will allow for more efficient panelization of the board. Also, steer clear of slotting when possible to avoid additional costs.
- Hole Size and Quantity
Holes and annular rings are just the opposite. Smaller holes require the use of more precise machinery and possibly additional chemical processing, increasing the price as a result. Use holes 0.4” and rings 0.3” or larger when possible to maintain lower cost.
Another obvious one, but the more complex your board is, the higher the pricing tends to be. Focus on designing a simpler board that’s utilized to its full extent without sacrificing component clearance.
- Copper Thickness
Where possible, try to keep copper to ½” thickness and PCB’s to 1/16” thickness.
Utilize Manufacturers’ Sourcing Services
Component sourcing requires a lot of time and dedication. Issues like obsolete parts cause headaches and complicate matters further. For that reason, it makes sense for smaller companies to rely on manufacturers to handle these duties.
Most PCB assemblers offer some sort of strategic sourcing service and can usually procure components at wholesale prices.
Deliver a Complete, Accurate BOM
The bill of materials is simply a list of parts and components used on a PCB. It contains critical information like part number, manufacturer’s name, quantity, and component replacements.
Be sure to accurately include all necessary information when submitting your bill to reduce back-and-forth time.
Don’t Skimp On Inspection
Inspection services usually add to cost, but the benefits are far more important. Many manufacturers offer in-house inspection, saving you from outsourcing to another third party company. The use of in-line inspection equipment or burn-in testing helps assure the quality of your product before it ever leaves the manufacturing floor.
Research which type of inspection equipment is best for your assembly. Services burn-in test, automated and x-ray inspection are all options that depend on your board’s component type, layer count and your own preference.