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use of skilled staff, perhaps leading to higher headcount than would otherwise be necessary; and designs taken to market in a less elegant form (due to restricted opportunity for design exploration) leading to reduced sales. Added to which are the immediate development-budget impacts of repeated prototype revisions. Any significant error can result in an unwanted prototype spin. Getting a conflict-free outcome on the first iteration is, in reality, only the first step. The design process will typically require a number of revisions and changes – even without adding any that arise from file transfer errors. As with any development, the cost of a change order rises sharply as the design proceeds. On average, Engineering Change Orders (ECOs) cost about €1,800 to implement during development, rising to almost €10,000 once a design has been released to manufacturing. There can be more subtle costs resulting from not having an automated data exchange, or not having confidence in the passing of accurate parameters. Tolerances and clearance allowances can be increased “just to be sure”, resulting in designs that are larger than they need be, using more materials and costing more in their BoM. In an era of ever-more compact and portable products, this is increasingly unacceptable. Or, designers can resort to traditional methods of ensuring fit and clearances, such as paper/card space models (“paper dolls”). Aside from the wasted resource of having skilled circuit and board designers spending their time making cardboard cut-outs, these cannot accurately represent aspects such as bend radii of rigid/flex assemblies – which can Circuit analysis & debug be completely modelled in current Altium Designer releases. More recently, technology has offered the alternative of a 3D printed space model to evaluate form-and-fit. These can be valuable as an aid to giving a real-world impression of how the end product will look and feel; but compared to an integrated ECAD/MCAD environment, they are a very limited verification vehicle to confirm fit and clearance data. A typical conventional design flow will start with a draft layout that may be set by mechanical (“it has to fit in this space”) or electrical constraints (“the PCB layout logically looks like this, design the enclosure around it”). In either case, if the first-pass PCB fits the draft case, with all components falling within their expected envelopes and no unexpected conflicts, then that layout can become “untouchable”. Any major revisions are simply too painful. With a seamless design environment, both electrical and mechanical designers gain the ability to explore alternative layouts and shapes in the virtual environment, without incurring the costs of a major design re-spin for every variation. A PCB layout must be populated with components, and a comprehensive and accurate component library is a further key aspect of the integrated design environment. For many years one of the impediments to operating an integrated PCB and 3D design environment was the limited availability of component data. If accurate dimension data was unavailable for even a relatively small fraction of the overall BoM, the effort of setting www.ew16_electronics-190x136_EE_Times_eetimes.Europe_com PULS.indd 1 Electronic Engineering Times Europe January 07.10.15 2016 10:31 30


EETE JAN 2016
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