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Cost impact for upgrades to aPriori Professional 2021 R1 SP1

Geometry or Cost Engine Changes that Could Impact Configured Digital Factories

The following changes might impact costing, even for Digital Factories that use earlier cost model versions.

  • NO IMPACT

Bug Fixes or Small Improvements to Prior Cost Model Versions

The following changes might impact costing for Digital Factories that use earlier cost model versions.

  • NO IMPACT

The Casting - Die process group may be impacted by changes in the Machining process group. Please review the impact assessment in the Secondary Machining process group.

Cost Model Changes that Do Not Affect Configured Digital Factories

The following changes do not affect costings with Digital Factories that use earlier cost model versions. The changes are available only in the latest cost model version.

  • PCB Array Nesting (impacts Material Cost and Cycle Time): This release assumes that, by default, small boards are arranged into multiple arrays on each panel, which helps support subsequent assembly of components to arrays of boards rather than to individual boards. A board is considered small if at least one can fit in an array. Default array size is specified by the cost model variables defaultArrayWidth (215.9mm in starting point Digital Factories) and defaultArrayLength (279.4mm in starting point Digital Factories).

    This change can increase material costs as well as cycle time for depanelization processes. Material Cost increased for about half the parts in a test set; the rest of the parts were unaffected because they were too large to be included in arrays by default. Of those that were affected, material utilization estimates decreased by an average of 33% on average and Material Cost increased by an average of 49%.

  • Labor Time Estimates: This release more accurately accounts for labor costs for the following processes:

    • Apply Photo Resist
    • Copper Plate
    • Cure Plugged Vias
    • Cure Solder Mask
    • DES
    • Desmear
    • Develop Solder Mask
    • Dissolve Unexposed Photo Resist
    • ENIG
    • Flying Probe
    • OSP
    • Oven Cure Layers
    • PTH
    • SES
    • Silkscreen Cure
    • Surface Prep
    • Tack Dry Solder Mask
    • Tin Coat For these processes, the number of operators has been set to 0 by default, and the only labor time modelled is for machine loading and unloading. As a result of this change, for a set of test parts, Labor Time decreased by 49% and Labor Cost decreased by 51% on average. Fully Burdened Cost decreased by 19% on average (ranging between12% and 28%). The amount of decrease for a specific part depends on the board size, number of layers, and number of layer processing cycles.

  • Surface Finishing Processes: This release provides two new surface finish processes: OSP (organic solderability preservative) and ENIG (electroless nickel immersion gold). OSP is now selected by default, instead of HASL (Hot Air Solder Leveling). The new default reduces finishing costs by up to 40%; Fully Burdened Costs decreases by only about 0.23% on average.

  • New Inspection Process: In this release, the final inspection process for PCB routings is now the new process Automated Vision Inspection. The new process replaces Automated Optical Inspection for the final inspection, but Automated Optical Inspection is still included in PCB routings for layer inspection. As a result of this change, Fully Burdened Cost estimates changed between -0.7% and + 5.8%, compared to the previous release.

  • Copper Plating: This release better accounts for costs associated with copper plating, improving estimates of copper thickness, board weight, material cost, and plating cycle time. Because estimates of copper thickness change in this release, board materials may change. In a test set, 50% of parts used fewer prepreg sheets, 7% used more, and 43% used the same number. Material cost decreased by around 2% on average.

    More significantly, the change in plating cycle time logic caused large increases in plating cost and fully burdened part cost. In a set of test parts, fully burdened cost increased between 10% and 45%, with an average increase of 23%.

  • Tack Dry Solder Mask: This release improves machine data and cost model logic for Tack Dry Solder Mask. As a result, for a set of test parts, smaller and less expensive machines were selected, and Fully Burdened Costs decreased between 0.5% to 2.6% compared to the previous release.

  • Via Plugging: This release adds support for plugging vias and contours to protect them against unwanted flow of solder during component assembly. Via plugging is disabled by default, but when enabled it impacts Cycle Time and Hard Tooling Cost. In a set of test parts, Cycle Time increased by only 0.19% and Labor Time by 0.82%. Total Hard Tooling Cost increases due to the cost of the stencil tool (with a default cost of $450, controlled by tool shop variable Stencil Cost); but note that the per-part increase in Hard Tooling Cost is small with typical part volumes. On average, Fully Burdened Cost estimates increased by 0.61% with via plugging enabled.