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AUGUST 2024 I DESIGN007 MAGAZINE 31 freight and finally, it will reduce the weight of your application. Panel Design and PCB Separation Suppliers use standard-size production pan- els between 18" x 24" to 21" x 26" but some of the newest factories are increasing to dou- ble-size production panels like 28" x 49" to optimize the production cost. Most PCBs are delivered in a customer-defined delivery panel designed to optimize the assembly cost. e optimization of the supplier production panel and the customer-defined delivery panel is very important to minimize material waste. Panel designs of PCBs with odd shapes can lead to undesired and inefficient material uti- lization. Engineering of these panel designs using rotated steps and nesting, resembling the old computer game Tetris, will oen lead to substantial cost savings. Rigid PCBs are mostly either milled on a CNC routing machine using a standard routing bit of 2 mm, prepared for depanelization by V-cut scoring, or a combination of both CNC milling and V-cut. e V-cut is cheaper and faster for both the PCB manufacturers and for the post-assembly depanelization, but it leaves a rough PCB edge, and ceramic components must keep a mini- mum 2–3 mm board edge safety distance to avoid undesired component stress during the V-cut depanelization. e depanelization of panels with break-tabs is more time-consuming since every break-tab must be removed by a mechanical cutter or the gentler routing method. PCB Complexity and Design Wiring Density e component size and wir- ing density are the main qualifiers of the PCB technology and layer count needed. Design features like minimum trace and space as well as minimum via-hole size limit the supplier range and thereby have a direct impact on the PCB price. We are oen asked specific questions about the cost impact of increasing the number of layers, adding microvia steps, reducing trace width and space, reducing hole sizes, etc. Layers vs. price: Going from two to four layers increases the PCB cost by approxi- mately 50% and for every two layers up to 12 layers will increase the cost by approximately 30%. At higher layer quantities, the percentage increase per extra layer pair declines. Standard ML vs. HDI additional microvia steps: Going from a standard 10-layer PCB to a 10-layer one-step microvia HDI increases the cost by 50–60%. Adding buried vias from lay- ers two to nine and microvias from layers two to three plus eight to nine increases the cost by 100%. Each additional microvia step increases the cost by 100%. Trace and space: At ICAPE, we recom- mend that mainstream low-cost products use 6 mil/150 µm trace and space since all suppli- ers will be available, including the really dedi- cated low-cost suppliers. Reducing the trace and space to 4-mil/100 µm may exclude some dedicated low-cost suppliers, increasing the cost. Reducing the trace and space to 3-mil/76 µm will further reduce supplier choice and will mainly only be possible for HDI suppliers. Reducing the trace and space to 2-mil/50 µm will only allow suppliers with UHDI capability. Minimum via hole size and tolerance: Most suppliers can offer plated through-hole 0.3 mm via-hole size without additional cost. Reducing to 0.2 or 0.25 mm via-hole size may increase