A few years ago I wanted to build a shed. I didn’t have any actual construction experience at the time, so I spent a lot of energy developing my building plan. I asked a lot of questions, ordered a set of blueprints, and purchased the materials. Now, with a well-built shed having served our tool storage needs through the last three winters, I can honestly say, “I love it when a plan comes together.”
Meticulous planning has also become essential when designing a new circuit board. Due to the current state of the electronic component supply chain, the confidence we once had in the availability of the necessary parts for our electronics has all but disappeared. Creating a new design today for long-term production requires specific and detailed strategies. Here are some ideas on PCB design BOM planning methods to help you avoid component shortages in your next electronics project.
Supply Chain Problems to Avoid
Short supply
Short supplyIt is no secret that the semiconductor industry has experienced some severe challenges brought on in part by changing markets in response to the global pandemic. Because of this, chip foundries have been unable to keep up with new demands, and inventories at some OEMs have dropped from a forty-day supply of stock on hand to less than five. This shortage has created a problem for some essential parts forcing designers to find alternative answers in parts and circuitry.
Lack of inventory
The electronics supply chain shortage is also affected by the global shipping problems. Some vendors cannot supply their customers due to inaccessibility to their standard shipping channels, while ships, ports, and trucking are bottled up. Many designers have found that the common parts they are accustomed to having access to are no longer available, and they have to scramble to find new resources.
Counterfeit parts
Another problem that has seen an increase over the past few years is the number of counterfeit parts flooding the market. In some cases, counterfeiters substitute false part numbers to repurpose general parts as higher-cost precision components. In other cases, old and outdated parts are being sold as new, and as always, there are a lot of plain pseudo parts on the market. OEMs have to learn how to recognize counterfeit parts and avoid the questionable dealers that sell them.
In short, PCB design teams have to learn new strategies to work around these problems, and next, we’ll look at a few that designers should consider.
PCB Design BOM Planning Strategies
Check part availability and prices before you commit to using them
One of the worst things you can do is use the “same old parts” you’ve always used without checking into them first. These parts may be delayed or have become too expensive, or they may simply be unavailable. You must confirm the availability of these parts before committing to a long-term production plan for your new design. It is also essential to validate the sources you are using for the parts to guard against counterfeit components.
Look for alternative options
If the parts you want to use are unavailable, consider some alternatives before you scrap the project:
- Alternative parts: You may find other components with similar functionality that you can use, or you may find combinations of parts that will give you the functionality you need. Although this may be more expensive, it could keep your design on track to meet your project goals.
- Redesigned circuitry: In some cases, a redesign of the circuitry may eliminate the need to use an unavailable part.
- Component redundancy: When using a part in a design that has questionable availability, you should consider ways to create alternative solutions within the circuitry. For instance, you could design the primary component and its alternative into the board or create a combination PCB footprint that would allow the use of either part in the same location. While this may not be the most elegant solution and depends on how much space you have on the board, it could end up saving you a lot later on if your primary part becomes unavailable.
Plan ahead
Don’t wait until the end of the design cycle to research the parts you need. You may run into parts with long lead times that won’t be available in time. It is best to start planning early on to coordinate the completion of your design schedule for when your components will be available for production. Thankfully, some electronic component specialists can help you with this type of PCB design BOM planning.
BOM Planning Resources
One resource you can turn to for help with your BOM planning is the contract manufacturer building your circuit boards. At VSE, we have a dedicated engineering and procurement team whose focus is ensuring that components in your design will give you the results you expect. Starting with a review of the BOM, our component engineers will verify that the parts you have specified will function as expected and are available for use. At the same time, our procurement specialists will source the parts you need to find the best prices and lead times.
Our involvement doesn’t stop there, though. Our design engineers will be reviewing your design for potential problems that can slow down the manufacturing process and report their findings and recommendations back to you. For those customers working with us on long-term builds of their circuit boards, we will continue to monitor the availability of the components you need. When the manufacturers of those parts change their life cycle status, as happens over time, our team will be ready to forward their recommended changes to you to keep production rolling.
