There is nothing quite like seeing your child’s eyes light up on Christmas morning as they unwrap that one gift they really, really wanted. For that moment, you are the greatest parent that ever lived! Moments like this make parenthood worth it and far outweigh the nights without sleep and changing dirty diapers. Your child does not need to know that you may have actually bought the last of that toy the night before and possibly deprived some other father of the elation you are feeling. Of course, you could have avoided this last minute stress by shopping ahead online.
Similar disappointment can come with designing printed circuit boards or PCBs. When designing PCBs or devices, one of the first orders of business is to select the components. At this stage, the primary concern is whether the chosen components will perform the desired circuit functionality. Although issues with the component procurement process can delay or even prevent your design from being manufactured, it is typical to give little consideration to acquisition at this point. Let’s take a look at the procurement process and some of the issues that may arise before investigating whether we can use online components to optimize the process.
The Component Procurement Process
Although it may not be often expressed as such, the component procurement process begins during circuit design and ends with the successful attainment of the correct components, ready to be assembled to your board. In fact, the procurement process impacts all aspects of PCB development. This perspective can be best appreciated by examining the steps of the process as they impact the design, fabrication and assembly stages of development.
COMPONENT PROCUREMENT PROCESS
PCB Development Stage
|Selection of components|
|Determination of component footprint|
|Component package and footprint match verification|
PCB Assembly (PCBA)
As shown in the table above, the component procurement process is a multi-step procedure. For each of these steps, some potential errors or issues can delay or halt PCB development until addressed or corrected.
Component Procurement Process Issues
The selection of components, Step 1, is usually the first action taken when creating the schematic for your design. For most components, it is common to rely on the database provided by your design software package unless specialized components are required. However, these databases can be out of date and contain components that are unavailable or no longer manufactured. Step 2 is the determination of the component footprints for your PCB layout. In the event that you have to create your own footprint(s), there is the risk of error in specifying and spacing pins and pads. The issues associated with Steps 1 and 2 are very easy to overlook during the design stage.
During your board’s fabrication, the footprints specified in your design file(s) are used to layout your PCB. If your layout is not compared against the component packages for your design in the component list or BOM, as Step 3 stipulates, your PCB layout could be incorrect. Additionally, for Step 4, the components acquired by your contract manufacturer (CM) are taken explicitly from your BOM. If any of these are unavailable due to a shortage, outdated and no longer produced, or do not match your board’s footprint, your PCB cannot be assembled. If your development has reached this stage with any of these issues, you will incur additional costs and lose valuable development time.
Procurement Optimization using Online Components
As described above, errors introduced during the component procurement process can manifest into significant issues during PCB manufacturing and delay or stop your design’s development. These issues can usually be traced back to the design stage where component information is selected or created but accuracy is not verified. Online components sourcing offers a more reliable alternative that can alleviate the issues associated with design package databases and manual footprint creation.
Purchasing components from online sources is certainly not a novel concept. In fact, you or your CM probably already utilize online sources, such as DigiKey or Mouser, for component acquisition. Employing this method can certainly assist you in ensuring components are available; however, to prevent procurement issues, this has to be instituted during design, specifically as part of your component selection process. In conjunction with selecting an online component, you must be able to acquire its particular footprint.
Depending on the online source, detailed information, including the PCB footprint or landing pattern, may not be available. In this case, the footprint has to be created manually, which can be troublesome, as previously discussed. Fortunately, there are online services that will generate downloadable component footprints for you. These include Altium’s EE Concierge and SnapEDA. The best online components services will enable you to source components and generate footprints for you. The most popular of these services is probably Octopart.
|Tempo‘s Custom PCB Manufacturing Service|
By utilizing online components services, you can eliminate the possibility of unavailable components, footprint error, unnecessary costs and lost development time. Doing so will enable you to truly optimize your component procurement process.
At Tempo Automation, we employ a custom quote tool that checks component availability prior to fabrication, thereby ensuring that you avoid unnecessary costs. We can help you get started on the best path for your PCB layout by furnishing information for your DFM and enabling you to easily view and download DRC files. If you’re an Altium user, you can simply add these files to your PCB design software.
If you are ready to have your design manufactured, try our quote tool to upload your CAD and BOM files. If you want more information on online components or how to utilize them to optimize your procurement process, contact us.