Issue link: https://iconnect007.uberflip.com/i/1101604
APRIL 2019 I DESIGN007 MAGAZINE 13 sifications. Merely having a bill of materials (BOM) doesn't tell us everything we need. The BOM doesn't give us an easy way to determine if we have a tall component too close to a rout- ed slot. Nor can it tell us if the AOI system is going to have difficulty seeing adjacent leads because of shadowing from tall components. But when the BOM is merged with the CAD data to make intelligent data, all of the neces- sary manufacturing checks can be automated. Product testability is another critical ele- ment of the deliverable to manufacturing. If the product is not easily testable, the ability to deliver cost-effective functioning boards is af- fected. In the same way, good DFM principals are now part of the design process, good DFT is needed throughout the process. Leaving it to the end, or not addressing it at all, delivers an incomplete product model to manufactur- ing, which affects deliveries, quality, and over- all product cost. The requirement for smart data is not lim- ited to conventional rigid PCBs. Smart data is required for flex and rigid-flex technologies because they use different materials and de- sign features. The DFM system must be able to know automatically where the bend area is as well as the stiffener, coverlay, and silver mask zones (Figure 3). We also need to think of smart data in terms of digitally modeling the manufacturing pro- cesses. This digital twin of manufacturing pro- cesses enables designers to benefit from in- telligent DFM concurrent with the layout pro- cess—the left-shift strategy. If designers can identify areas to improve their PCB design while they are doing the design, they greatly reduce the number of revisions necessary to ramp their designs to volume production. The digital manufacturing twin of process capabil- ities makes it easier for them to achieve this optimization without having to possess the Figure 2: Intelligent data allows DFM software to automatically recognize an HDI design. Figure 3: Proper DFM of flex circuits requires intelligent data from EDA to systematically identify the various zones of material.