As technology advances, PCBs (Printed Circuit Boards) become more complex which means product managers and designers need to find and utilise PCB Assembly houses, who can meet their assembly requirements.
Less investment cost
PCB Assembly is a complex process requiring specialised equipment, trained personnel and a strong quality management system to ensure the final assembled product works as intended. Even a simple PCB with SMD (Surface Mount Devices) can require complex machinery to ensure quality. In our experience a reliable basic assembly line with the bare minimum of a Stencil Printer, Pick and Place Machine & reflow oven would be in the range of $400k USD. This is excluding a clean room, factory setup, AOI (Automatic Optical Inspection), X-Ray inspection etc.Saving Product Cost
Assembly Houses are setup to manufacture and assemble products as efficiently as possible. For this reason, the cost of your final assembled product can be competitive over assembling yourself. This is especially true with low/medium volume builds where the internal investment cost doesn’t add up.Local vs Offshore
Being an assembly house ourselves we see customers onshore their PCB assembly requirements. However, most of the designs we produce for manufacture are low/medium volume and can be complex. This isn’t to say offshoring isn’t a good idea, however due diligence is required when using an offshore assembly house prior to engagement.Lowers PCB Risk and Failure Rates
Most assembly houses do a DFM (Design for Manufacturing) analysis prior to assembling or even quoting a job. This is to ensure the final assembly matches your requirements and that the risk of failure is lowered. That being said it’s fairly common for issues to occur during assembly and there are certain standards to ensure the assembly is acceptable, IPC 610-A is a fairly common one. So don’t be too surprised to see some rework here and there. Providing your assembly house with a ICT (In-circuit tester) will allow them to properly test PCB after assembly, if there are issues their rework technicians are likely highly experienced and will be able to fix/rework a failed board.Faster and more reliable time-to-market
NPI (New Product Introduction) processes can be complex especially for high-reliability systems and therefore to ensure a smoother run to market using an PCB assembly house might make things a lot simpler. Most of their lead times are highly accurate and generally very quick relative to other types of manufacturing i.e. injection molding / tooling.Tap into specialist skills and equipment resources
Experience is key to understanding and troubleshooting a PCB assembly line and the skills required to become a proficient SMT line operator can take years. Using a contract manufacturer allows you to tap into this experience, furthermore a good assembly house will provide you with manufacturing feedback so you can modify your design to ensure a more robust manufacturing process. This could be adding additional fiducials, modifying PCB footprints/land patterns etc. Equipment also plays a large role in ensuring a high degree of quality control, for example using an X-Ray machine to inspect BGA’s or 3D inspection for solder paste volume can more greatly reduce defects.Growth & Scalability
It can be hard to determine how well a product will sell once it hits the market, but by having an established relationship with a PCB contract manufacturer will ensure scalability and growth, especially during a product ramp up stage.Focus on NPI & product development
As mentioned setting up an inhouse manufacturing facility is very complex and so your time/efforts might be better spent on focusing on the actual product and ensuring the PCB is compliant and properly tested prior to product sales.Post-market services and obsolescence/EOL management
Contract manufacturers and PCB assembly service delivery companies usually have an in-house procurement team who have custom software to ensure the on-going supply and availability of components and also suggest similar/replacement components.BOM and Stock Management
BOM (Bill of Materials) management can be tedious and complicated, especially if the final PCB assembly contains many unique components. Often managing this with simple spreadsheets doesn’t suffice, so most assembly houses use sophisticated sourcing software with APIs that communicate with various distributors and in some cases chip/component manufacturers. So, it’s often easier to leave it to them for finding and sourcing your components. Beware though we have seen many instances of counterfeit or used IC’s being loaded on PCBs, if in doubt supply your own components directly to the contract manufacturer.Compliance and risk mitigation
There are numerous standards for PCB assembly and stating these specifically when ordering through an assembly house will ensure compliance. Some standards include:- Lead free assembly / RoHS
- IPC-2581
- This is a great standard for ensuring you provide the assembly house with the right documentation
- IPC-A-610
- Provides the requirements for acceptance of electronic assemblies
- IPC-JSTD-001
- Provides guidance on the use of x-ray to inspect through-hole solder conditions that are not visible by any other means
- IPC-7711
- Rework/Repair Modification program covers common rework and repair techniques.
FAQ
What are the advantages of outsourcing PCB Assembly?
- Lower cost, faster turn-around and less risk
Who benefits the most from outsourcing?
- Unless you are trying to manufacture your own products, in which case it might be worth investing in in-house equipment.
What files are needed to get a quotation?
- Everything stated in IPC-2581, but more generally
- PCB Gerber Files
- BoM
- PnP / Centroid Files
- Assembly drawings
- Testing procedures
Should the same facility that manufactures the boards also load my PCB Assembly?
- Most PCB bare board manufacturers aren’t setup for PCB Assembly. Or they may outsource it to a trustworthy agent. Either way, do your due-diligence prior to selecting an assembly house.
How long does it take to assemble a PCB?
- Assuming the components are in-stock the assembly process for low/mid volume is fast. The machine in our facility can run at up to 40,000 components per hour. More time is spent re-working and completing through hole soldering.