Knowing when to source materials can accelerate the schedule of your PCB build and significantly reduce the transition from engineering design phase to product delivery. Purchasing material too early can result in procuring material that may be unnecessary for the final design. Likewise, waiting too long to begin the purchasing will likely lead to an unnecessarily extended production time. In purchasing timing can make or break a production schedule. Not every build is the same but the following guidelines can provide a path to efficient and timely purchasing decisions.
When a design is 50% complete, it is time to get a budgetary quote and DFM from the PCB fabrication source and an assembly provider. At that time, ask the assembly provider for their list of consigned material requirements. These are an outline of the documents, labeling and material requirements for the assembly process to proceed efficiently and without significant additional preparation.
When the design is 80% complete and the major components have been chosen, it is time to get the initial quote for the component material kit. The list of material requirements for your chosen assembly provider should be provided with the RFQ. The material quote and feedback should be provided within 4 hours to 48 hours from the request.
The feedback on the initial Bill of Materials quote should include:
- any obsolete components and suggested options for replacement
- lead-time for components and suggested options for items which will impact the initial build
- an alert for any components found identified by the manufacturer as End of Life
- any components which need additional prep for the assembly process and estimated time
Resolve any issues from the feedback on the initial BoM; finding replacements or approving suggested alternate components. Components, which are design-firm and have a lead-time, should be authorized to be purchased so the component lead-time and finalizing of the design / layout can run concurrent.
With the design 100% complete, the board fabrication and the remainder of the components can be ordered.
If you need help planning your PCB assembly or would like to discuss your upcoming project with a professional project coordinator, send me a note or call. We’ll be glad to discuss how we can help to improve your product delivery timeframe.