BOM Analysis: My Favorite Tools for BOM Review

Getting caught with unsourceable components in a bill of materials (BOM) is more common than you might think, especially if you delay the BOM review until the last moment. Even with all the real-time supply chain tools provided in EDA software, designers can still get to the stage where they need to place an order, only to find parts are suddenly out of stock. A related issue is obsolescence, where parts included in a hardware BOM suddenly go into EOL (end-of-life) or become obsolete without any notice from the manufacturer.

If these events happen, you'll have to do a redesign and rework the board at some point. The time required to implement a redesign will be greatest when that redesign needs to happen right before ordering parts for a build. Instead of waiting until the end of your design cycle to check a PCB BOM, it's much better to perform periodic BOM reviews at strategic points in the PCB design process. A BOM analysis that catches simple parts swaps early, such as while you're still designing schematics, is preferable to a situation where placements and routing have to change to accommodate a component swap.

BOM reviews don't have to be arduous tasks if you have the right supply chain data and BOM checker tools. In this article, I'll show you how I do BOM reviews and the information such reviews can quickly offer as I move through the PCB design process.

What Is a BOM Review?

A BOM review involves a periodic check of the BOM for a PCB project for any changes in inventory, pricing, lead time, and life cycle status. The goal of a BOM review is to identify unsourceable components or incorrect information in a BOM before a PCB is put into production. By doing this before a design is completed, it will be much easier to minimize any redesign work if a BOM analysis uncovers unsourceable components.

In many instances, a BOM is rarely reviewed between the time it is finalized and the time a design is placed into production. By waiting until the design is finished to start looking into the supply chain, designers put themselves at risk of redesigns just to accommodate last-minute component swaps. Performing reviews between the completion of schematics and the purchasing of components allows you to catch these required swaps early. This way, swaps can be implemented before the layout and routing are complete, minimizing the impact on the design, thus reducing design cycle time and cost.

My Favorite BOM Tools for Lightning-Fast BOM Reviews

Let's be honest: no one likes doing design reviews, whether it's a BOM review, schematic review, or PCB layout review. They take a lot of time, and oftentimes you don't actually know what you're looking for during the review. In a BOM review, things can be done much faster with the right BOM analysis tools and by setting aside time for a review in your design process.

Distributor Websites

Some distributor websites will allow users to upload a PCB BOM file, usually in Excel or CSV format. This is basically the process you would take when starting a new order; once the BOM is uploaded, the platform will search through the company’s inventory and match it to the parts in your BOM. The distributor’s website will then tell you which parts in the BOM cannot be procured due to inventory shortages or life cycle status.

You can use your distributor’s website, such as the list feature in Digi-Key, to spot out-of-stock and obsolete parts

The above screenshot from Digi-Key shows their list creation system. Parts that are not in their inventory or are obsolete are flagged for the user. You can upload your BOM at any time before the completion of the project and perform this exercise, reducing the time needed to implement swaps for those parts.

BOM Tool in Octopart

The problem with going onto distributor websites is that there are dozens of distributors, and not all of them have a BOM upload system like Digi-Key or Mouser. Instead, you need a BOM checker that shows you inventory across all distributors.

This is where I prefer to use the BOM tool in Octopart. The BOM tool allows you to upload an Excel sheet of your BOM, quickly map columns, and search through distributor inventory for availability. You can select multiple distributors to scan and search for parts, and you will get the same information as you would find on a single distributor's website.

This view in the BOM tool shows EOL/NRND/obsolete parts

What about a third-party supply chain platform? I think most designers don't realize that many third-party logistics providers (3PL) actually pull all of their supply chain data from a data aggregator, and in most cases, that data aggregator is Octopart. If your 3PL provides a BOM view that shows sourcing problems, take advantage of it for a BOM review! 

ActiveBOM in Altium Designer

One very useful tool in Altium Designer that can help you run a BOM review is ActiveBOM. The purpose of ActiveBOM is to create a PCB BOM that is directly linked to supply chain information, and the ideal time to create this is right after schematics are finalized. However, you can still check ActiveBOM at any time during your design process, and this on-demand BOM analysis will allow you to identify unsourceable components before the design is completed. Once those are identified, they can be immediately swapped out of the design, and a redesign can be quickly implemented.

When you open an ActiveBOM document (.BomDoc extension), the ActiveBOM tool will scan supplier availability for each item in your BOM. You will then see this displayed on screen along with total inventory numbers and price estimates.

ActiveBOM verifies sourceability for each line in the BOM

ActiveBOM works with a batch size of one, so it only applies to your PCB project. It is also accessed inside Altium Designer; this is fine for engineers but is not ideal for other stakeholders, such as managers or procurement. This is where Altium 365 provides an even better solution.

BOM Portal in Altium 365

The BOM Portal in Altium 365 performs very similar functions as ActiveBOM, but it provides the benefit of being accessible in the cloud. If you host your PCB project in the cloud in Altium 365, the project can be shared with other stakeholders so that they can view and provide feedback on design data. This includes a BOM review, which can be performed throughout the product design phase in the BOM Portal in Altium 365.

The BOM Portal in Altium 365 allows teams to perform a BOM review in the cloud at any time

The process for implementing a BOM review in Altium 365 is simple:

• Open the project in the BOM Portal
  • Check component lifecycle status
  • Review supply chain risks
  • Verify compliance requirements
  • Check availability across suppliers
• When issues are found, BOM Portal provides direct actions
  • Resolve issues by yourself (select different suppliers or add alternatives) or 
  • Place a comment for the engineering team to mitigate the issues 
• The design engineer will then get a notification about such highlighted issues
• The design engineer can change the parts in the schematic and PCB layout within Altium Designer
• The updates provided by the design engineer can then be transferred to the managed BOM in BOM Portal

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 hardware 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 a try. We think you'll experience a seamless transition to a new workflow that expands your reach and capabilities.