Price Considerations for Flexible Circuit Design

For the most part, designers understand what types of constructions and design attributes are “non-standard” and add cost to their design.  Flex circuit and rigid flex design is similar with a few “odd ball” factors thrown in.  We have compiled a short list of design attributes and how they impact cost.  For more detailed information on costs or for a free copy of our design guide, please contact us!

 Low Cost Factors:

  • Complex routing and scoring
  • Edge routing
  • Strain relief
  • LF vs AP materials

 Medium Cost Factors:

  • Aspect ratio > 10:1
  • Drill hole count > 30K
  • Non-FR4 material in the rigid areas
  • Drilled holes < .012”
  • Stiffeners (rigidizers)
  • Added tear stops
  • Line width and space < .005”
  • Button plating
  • Controlled impedance
  • Annular ring (pad < drill + 12)

 High Cost Factors:

  • Advanced technologies
  • Buried vias
  • Layer count
  • Material utilization
  • Selective plating
  • Buried access (ZIF connectors)
  • Line width and space  < .004”

 Cost Trade Offs:  general rule of thumb 

  • Use smaller line width/space before adding layers
  • Investigate how the boards will fit in the production panel for material untilization
    • do not forget about nesting flex or straightening a bend and folding after parts are removed from the panel
    • LF materials are lower cost than AP materials, but the increase in acrylic resin in a via stack can reduce reliability due to an excessive CTE-Z

 Involve your PCB supply chain partner early in the design phase to ensure the most reliable, cost effective design that will meet your specific requirements!

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