While searching for a PCB contract manufacturer to partner with for building your circuit boards, establishing a high level of communication and trust is tantamount to a successful final product. Whether a novice or experienced in design, some subtle layout choices can develop into major manufacturing problems further down the road if left unaddressed. To optimally address design intent and manufacturability, designers or design teams need to be able to identify the best PCB assembly services available.
PCB Assembly Best Practices
Sidestepping production issues before potential problems arise saves time, money, and frustration. PCB assemblers focusing on quality will deliver a superior board in minimum time while improving the design for current and future iterations.
Comparing Best PCB Assembly Services |
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|---|---|---|---|
| Substandard Assembly | Good Assembly | Best Assembly | |
| Design Review | Lack of all-encompassing review leads to excessive respins and time lost to redesign. | Review can assess where design needs to adapt to aid manufacturing. | Identifies ways to improve manufacturability at the design stage. |
| BOM Review | Takes BOM as-is and does not attempt to navigate the market shortages more than necessary. | Uses bulk purchasing power and cultivates business relationships to leverage sourcing and procurement. | Stays ahead of market trends to gauge the obsolescence of parts and keeps an ample supply of components. |
| Documentation | Poor, lacking, or inaccurate documentation can cause errors in production and design. | Large, legible, and unambiguous manufacturing files and design documents foster clear communication. | Documentation and file encoding will preserve design intent and capture the necessary details for future revisions. |
| Testing | Coverage is not comprehensive or results aren’t optimal. | Practices aim to maximize board quality using iterative production methods. | Testing is proactive and limits defect escape and detects it at the earliest occurrence. |
Common Problems with PCB Contract Manufacturers
With the high degree of technical expertise and equipment in PCB production, the designer or design team and the manufacturer must coordinate effectively to realize design intent. There must be a rock-solid foundation between designers and CM, especially when a design is gradually building from proof of concept to NPI (and further prototypes). Unfortunately, not every CM builds to equal standards. Look for these issues early that may suggest an ill-suited partnership for manufacturing:
- Inconsistent manufacturing practices – Is there a high variance in the performance or yield of the board?
- Undocumented changes – Poor documentation means having to discern informal changes for future revisions, which becomes especially troublesome if production transfers to another manufacturer.
- Customer returns – Before the boards are fit to leave the shop, designers must be confident that they undergo extensive analysis to minimize end-user frustration.
- Poor documentation practices – Fully updated design documentation is crucial to maintaining the link between past and future board iterations.
- Excessive respins – Beware of the “Whack-A-Mole” manufacturing method, which resolves poor practices post-production rather than circumvents them before fabrication and assembly.
- Incompatible CAD tools/databases – Translating documents and files can take time and introduce errors at the initial design stages.
Designers or design teams can avoid these problems by choosing to partner only with a CM or CMs that provide the level of quality necessary for a successful build. Not only do manufacturing and testing capabilities need to be top-notch, but they should also reduce the number of unnecessary (i.e., unexpected from the manufacturing side) re-spins for a product in the development stage. Minimizing the number of redesigns will save money and time, allowing designers to bring products to market sooner than a less experienced or rigorous assembly shop.
The Best PCB Assembly Services Are Proactive, Not Reactive
To successfully realize projects, a CM requires adequate staffing of trained personnel who work with designers on optimizing the board layout before it reaches the shop floor. When evaluating a CM, ask questions about their processes, quality, and service, and establish criteria to qualify them early in product development. Many CMs also welcome facility visits to build an in-person rapport; designers should take advantage of these walkthroughs to minimize the production cycle time. Designers can facilitate a smooth manufacturing workflow by investigating some core CM practices:
- Component analysis – CMs need a methodology for tracking obsolete components in a bill of materials (BOM) or otherwise depreciated components. A CM’s ability to quickly replace, source, and procure alternate components can be the difference between meeting production schedules or waiting for part resupplies.
- Design for manufacturability (DFM) review – Any features that complicate the board’s manufacturability will require engineering resources to resolve. Implementing DFM may include having the CM make layout corrections while preserving the board’s design intent.
- Design for test (DFT) review – A CM must be able to review designs for testability and make recommendations for corrections, especially for mid-to-high-volume productions. Proper test fixture design and programming will minimize testing turnaround times.
The baseline expectation for a competent CM is a fully defined assembly process from start to finish. This method would include everything from component procurement through soldering. Supporting processes such as quality control and inspection points throughout manufacturing flag potential defects at the earliest point of occurrence, minimizing losses owing to yield, materials, and labor. Once assembly is complete, a design will undergo thorough testing. Testing services should be all-encompassing to ensure complete inspection of the PCB, from ICT and flying probe to a full functional test.
Your Contract Manufacturer Bests Even the Highest Expectations
The best PCB assembly services require two-way communication to accommodate the design intent while maximizing producibility and minimizing cost. A CM’s goal is to deliver an assembled board back at the highest level of quality possible. That means collaborating closely throughout a project’s manufacturing lifecycle and running BOM, DFM, and DFT evaluations to optimize designs for production while meeting all form, fit, and function requirements. At VSE, our engineers are committed to building electronics across many life-saving and life-changing industries for our customers. Working closely with our valued manufacturing partners, we endeavor to realize your NPI or large production volume goals.
