“Timing is everything,” or so I’ve heard on many occasions concerning various types of situations. Two occurrences that do not temporally overlap to some degree cannot directly impact each other; however, the past occurrence may residually impact the latter. For instance, applying design for assembly (DFA) rules and guidelines can have a tremendously positive effect on the later-occurring PCB assembly process.
PCB assembly includes tasks designed to securely mount your SMD and through-hole components to your fabricated board for both the prototyping and production stages of product development. Ensuring the availability of required components during these stages is critical for PCB development efficiency. In this case, timing is everything as the component lifecycle needs to align with the prototyping and production stages of PCB development. Misalignment may result in delayed PCB manufacture, engineering change orders (ECOs) for redesign and additional costs. However, these contingencies can be avoided by understanding what the component cycle is and exactly how it impacts PCB development.
What is the Component Lifecycle?
Most manufactured devices that make it to market have a product life cycle. Not to be confused with the operational life cycle (the period during which the product can continually perform its function), the product life cycle is the period from the introduction of the product in the market to when it ceases to be manufactured. A lifecycle can also characterize the components that comprise PCBs. A component lifecycle can be divided into six stages:
|COMPONENT LIFECYCLE STAGES|
|Introduction||Low production, high production costs.|
|Growth||Market acceptance and higher production. Usually accompanied by a lower price.|
|Maturity||High-volume production and stabilized price.|
|Decline||Decreasing demand and declining production.|
|Phase-out||Target stop date set for manufacture.|
|Obsolescence||This occurs when technology exceeds the component’s capability.|
As shown above, the production, and therefore the availability, of a component varies over its lifecycle. Now, let’s see how this variation impacts your PCB development.
The Component Lifecycle Impact on PCB Development and Production
Although typically not expressed as such, PCB development is also characterized by variance in the number of boards required at different stages. For prototyping, the number of boards may range from a few to hundreds depending on how close the design is to finalization. For production, PCBs have life cycles similar to other manufactured products. In fact, PCB life cycles typically mirror the life cycles of the electronic devices in which they are deployed.
More component availability is undoubtedly necessary for production; however, component selection occurs during design, which precedes prototyping. Therefore, selecting components such that adequate numbers are available throughout PCB development and production is an essential aspect of project management. The best, or less risky, way to ensure adequate supply is through component warehousing or advance procurement of the estimated number of components to sustain production for a substantial time period.
This period should be long enough to facilitate the selection of substitute components and testing and verification (if necessary) of a new design without interruptions to the production cadence. The drawback here is the upfront cost, which may be quite significant depending upon your design complexity and number of components.
As it may be cost-prohibitive or otherwise impractical to warehouse projected components for development and production, an alternative strategy for guarding against component shortages that takes the component lifecycle into account is warranted. The table below lists the stages of the component lifecycle where components can be safely selected for PCB prototyping or production.
|COMPONENT LIFECYCLE||PCB MANUFACTURING STAGE|
As seen above, adequate numbers for a component should be available from Introduction through Decline to perform prototyping. However, the Growth and Maturity stages of the component lifecycle are the only periods where you can be reasonably sure that adequate numbers of components are available for production. If you opt to select components for prototyping that are in the Introduction stage of the component lifecycle, there is some risk that a delay between the time you’re ready to move into high volume PCB production and when sufficient supply is available will exist. Similarly, if you choose components in the Decline stage of prototyping, there is a risk that significant supply may not exist when you’re ready to move to production. To combat this shortage, it may be feasible to perform a Last Time Buy to provide time for alternative or substitute components to be identified and procured while maintaining your production schedule. Both of these selections should be made with the knowledge that there may be risks when transitioning from prototyping to production. It is recommended never to use components that have already reached Phase-out or Obsolescence.
Component selection is a significant part of the PCB development process which, if done poorly, may result in delayed PCB manufacturing for prototyping and production. However, understanding and using the component lifecycle enables you to make selections to improve the efficiency of your board’s manufacturing.
|Tempo‘s Custom PCB Manufacturing Service|
Tempo Automation, the leading turnkey PCB manufacturing company in the industry, utilizes custom software to verify component availability and uses only reputable suppliers. We also furnish information for your DFM and enable you to quickly 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 the component lifecycle or how to incorporate it into your design to minimize the likelihood of component shortfall issues, contact us.