MEP EP#316: Chunk 2 Chunk Current Returns

Circuit grounding - How big is too big?

• Stephen has a new design that is trying something very odd
  • Planes that connect to the star
• Difference between different grounding techniques
• 8 layer monster board with multiple power supplies - low noise
• Parker likes to think of these problems as the extremes of certain examples as a way to think about what happens
  • Take a "star" topography ground for instance
    • Make the trace lengths that connect to the "star" really small
    • Make the star point really "big"
    • This is vias connections direct to a plain

Coilcraft has “Elevated” inductors

• Parker found this tweet by Lukas Henkel showing coilcraft has inductors that are elevated off the PCB which allows placing parts under the component
• Coilcraft XAR7030 series
  • Unique off-the-board design provides 1.5 mm clearance for parts to be mounted underneath
  • Magnetically shielded for high density applications
• Torex Semiconductor has combined switch mode controllers and inductors to build micro DC/DC converters
• PCB Assembly problems?
  • Should XYRS now have a Z height?
  • This is typically on the CMs to "get it right"
  • Probably best to let your CM know what your doing in this case to reduce confusion