Strategies for Boosting Procurement Efficiency in PCB Component Sourcing

How many times have you uploaded your BOM to a distributor website, only to find that half of the parts can't be procured or will be stuck on backorder? You're not alone if this has happened to you. The industry moves very quickly, and if you're ordering at levels that require you to procure through distributors, you shouldn't be surprised when some items in your BOM go obsolete, reach end-of-life (EOL), or go out of stock. This can all happen without any warning, leaving you with design work to complete even after the PCB layout is finalized.

Although it's rare to immediately put a board into production with zero BOM modifications, it's possible to minimize the time and headache involved with the right procurement process. Every company's procurement process will be different, but we have compiled some tips on how to structure your BOM review process to minimize the friction involved in sourcing PCB components.

Implement a BOM Review Process

Delays in PCB component sourcing often happen because something unexpected is lurking in your BOM. At some point, the BOM was ideally perfect, with no obsolete or out-of-stock parts listed for purchase in the design. However, over time, things change, and problems can accumulate if a BOM review is not performed.

This leads to our first piece of advice: perform a BOM review at strategic points during a PCB design project. There are three key points during a project where someone on your team should perform a BOM review:

• After schematics are finalized and reviewed
• After component placement but before routing
• After the final cleanup of the PCB layout but before purchasing

No one likes meetings and review sessions, as they take up a lot of time and are not guaranteed to produce actionable outcomes. Keeping the number of review sessions to three makes this a natural part of the process of developing a new product. Keeping the number of reviews low also minimizes time requirements for members of the design team, allowing them to focus on product development.

BOM reviews can be as shallow or as in-depth as you like. If your team is more organized, you might consider scheduling periodic BOM reviews to ensure prices and available part quantities are meeting targets. Ultimately, the goal is to locate parts in the design that can't be sourced, or that may cause some other problems during assembly. It's also a good idea to check that the data in the BOM is correct, such as having complete part numbers and matching component descriptions based on vendor data.

Include Alternates in the BOM

A BOM review applies to the parts that will appear in a design, but it can also be used to spot availability for alternate parts. If alternates are included in a BOM as their own line items, you can immediately spot the availability of alternates should a desired part go out of stock. Alternates can then be immediately placed into the design, allowing your team to continue as normal.

Alternates could include a broad range of parts. These could be:

• Parts with different temperature ranges but the same part number group
• Parts in the same part number group but with different features or packaging
• Parts from a completely different manufacturer in the same package
• Different parts with different packages or pinouts

Those options are listed in order of importance and convenience. No matter which one you choose, pick an approach and stick with it if you are specifying alternates in the BOM. If listed as their own line item, they should include a suffix on the designator and should not be placed on the PCB unless needed. You could also specify these as parameters on each line item so the alternate will appear in its own column.

A Single Source of Truth for BOM Revisions

Teams with multiple designers who are looking at a BOM may soon find that their copies of the BOM are out of sync because they are not relying on a version control system for PCB projects. To ensure you have a single revision history for a BOM, a design team can take two approaches:

• Track copies of a BOM export in version control
• Place the entire project in version control and regenerate the BOM on each review

Without a doubt, the second option is the best. If you're already tracking your project files for your PCBs in version control, then every regeneration of the BOM reflects the most recent revision to the design data.

This is why a tool like the BOM Portal in Altium 365 is so important for PCB design projects. Each time you open the BOM Portal, the tool creates your bill of materials directly from your project data and polls real-time supply chain information into the BOM. This means you can immediately see lifecycle status changes, price changes, and inventory changes as you perform a BOM review. Once any problems in the BOM are identified, users can place comments on affected parts directly inside the schematics and send these back to the designer for review.

By the time your team is ready to make purchases, most of the major problems that create time delays in PCB component sourcing and manufacturing will have already been addressed. Catching these problems in your BOM and your CAD data early will help your company stay on schedule and on budget. If you're ready to learn more, open up your Altium 365 workspace and give the BOM Portal application a try. You'll experience a seamless transition to a new workflow that expands your reach and capabilities.