Embedded computers are usually assembled on order, with the components chosen depending on the features required. This means that the component list can change quite a bit through a product’s lifecycle, as better or cheaper parts become available.

In many cases, this isn’t much of an issue, since you only care about the end performance. But there are situations where it is necessary to ensure that the deployed device maintains the same specifications throughout, either due to regulatory or maintenance reasons.

How do we achieve this? When do we need to? What are the pros and cons of such an approach? Let’s find out.

What is a Bill of Materials?

The Bill of Materials (or BOM) is simply a complete list of all the materials and components required to manufacture a product. For an embedded computer, this translates to all the parts needed to assemble it. The board, the chip, the memory, the storage, and any other additional modules.

Normally, the BOM is generated before placing an order, and does not necessarily remain static throughout the product’s lifecycle. Especially for embedded computers, where we often see 10-15 year lifecycles for a computer.

It is possible that cheaper or better components come out in a few years, which means the next time there is an order for replacing the systems, a new BOM is generated using the latest parts. But that also means that the new systems will be significantly different from the existing devices, which might be a problem in some situations.

Why Would a Changing Bom Be an Issue?

Changing the configuration of an embedded computer in use can be a problem in various scenarios. One is in applications with strict regulatory requirements.

PCs used in medical applications, for example, have to adhere to rigorous safety standards before being approved for use. If the device’s Bill of Materials is then changed later, the new configuration has to be certified again.

Regulatory compliance aside, a varying BOM might not be ideal in terms of compatibility as well. Repairing any broken-down computer is trickier when there are multiple variants deployed, which creates issues for sourcing replacement parts. Their differing capabilities might even translate to varying life cycles, creating a further headache in managing the eventual phase-out of the system.

BOM Freeze: A Way to “Lock” Device Specifications

The simplest solution to prevent any such issue from arising is to freeze the Bill of Materials once the device is certified and approved. This means that the components of the computer are fixed at the initial configuration, no matter what new alternatives might present themselves later.

Of course, it is not as simple as just deciding on paper. A BOM freeze must be implemented throughout the supply chain, from the companies producing the components to the Original Equipment Manufacturers (OEMs) assembling the boards. This involves rigorous inspection at every stage, ensuring that none of the parts vary from the specifications in the frozen BOM.

This also involves partnering with vendors that can uphold a stable supply throughout the product’s lifecycle. In cases where that is not possible due to a component being phased out of production, it is bought in bulk to meet the potential needs throughout the timeframe. Another way is to decide on alternative parts in the original BOM itself, which are certified alongside the first testing process and can then be used interchangeably later if supply issues arise.

How Does a BOM Freeze Help?

Freezing the Bill of Materials of an embedded computer is like locking down its blueprint – it ensures reliability. Products like medical computers go through extensive testing before being actually deployed, and companies don’t want to go through it all again before exhausting the computer’s complete lifecycle.

A BOM freeze makes that possible, saving both the regulatory hassle and the expenses that would be incurred in constant upgrades. It also makes troubleshooting and fixing the setup easier as its specifications remain the same throughout its lifecycle without any major changes.

Of course, implementing a BOM freeze is impossible without partnering with an embedded systems provider who is willing to walk the extra mile. Your provider needs to properly document all the components making up the PC through every step of the supply chain, and consistently ensure that no changes are made, even when acquiring them at scale.

Here at Global American, we are committed to fulfilling any regulatory compliance required by our supplied computers, including a BOM freeze. We have experience working with medical systems as well, and know exactly how to ensure a stable production cycle for such PCs. Contact us if you are looking to procure embedded systems for medical facilities or other applications that require long lifecycles without any supply uncertainties!