Issue link: https://iconnect007.uberflip.com/i/1470111
64 DESIGN007 MAGAZINE I JUNE 2022 Besides the typical technical product devel- opment questions, there are several questions that we will also flush out early in the process: • What are the product specifications that must be met? • Are there geographic or ITAR restrictions? • What are the projected prototype and production volumes? • Do you have an approved vendor list (AVL), incumbent board fabricators, and/or contract manufacturers? • Does the product require RoHS compliance? • Do you have any single source components or custom components on your bill of materials (BOM)? • What is your project's target completion date? Addressing these questions helps identify all the DWM stakeholders so that we can begin communications to assure that we are in sync. e goal is to validate the decisions early in the design process rather than later, or during fab- rication or assembly when problems are much more expensive to resolve. It is important to match the technical requirements with manu- facturers whose process capabilities are well aligned with the technical requirements. Communication: Saving Money, Resources For instance, receiving guidance from your PCB fabricator on laminate material options, costs, and availability issues is very beneficial. Establishing a board stackup that meets the technical requirements and is manufacturable is a prerequisite for successful high-perfor- mance or high-volume designs. Identifying coupon requirements, test- ing, panelization, thieving, and assembly rail requirements helps to streamline the PCB fab- rication process and promote efficient assem- bly of the printed circuit board. Designing with blind and buried vias can increase the fab processing time but it may enable a PCB to be designed in fewer layers, which can more than offset the increased processing time. is could be very significant for high-volume prod- ucts. Addressing these requirements upfront enables the design to move smoothly through the fab and assembly processes. Circuit-to-panel optimization should also be addressed during the design phase, particularly in higher-volume requirements. Panel utilization is dependent upon the panel sizes supported by the fabricator. Copper thieving is oen added to the layers of the PCB to provide a better balance of copper to prevent the boards from warping. Non-functional plated through-holes may be eliminated to reduce the drill time and potential for fallout due to broken drills. All these issues are addressed between the design engineer, the layout designer, and the fabricator. Particular diligence is required to manage the lifecycle analysis during the component selec- tion process. Component availability issues are crippling product development and manu- facturing around the world. We highly recom- mend that the design process should include the engineer providing alternate components on the AVL and BOM. Providing component alternates can give the contract manufacturers the ability to manage availability issues with- out involving the OEM for approvals, which can slow down the process. Circuit-to-panel optimization should also be addressed during the design phase, particularly in higher-volume requirements.