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PCB stackup example – minimum track, clearance, VIA …

Here is the PCB stackup what I normally start with + requirements for minimum VIA, track, clearance and impedances.
  • 12 Layers:
    • L1 – Signal
    • L2 – GND
    • L3 – Signal
    • L4 – Signal
    • L5 – GND
    • L6 – Powers
    • L7 – Powers
    • L8 – GND
    • L9 – Signal
    • L10 – Signal
    • L11 – GND
    • L12 – Signal
  • Required impedances
    • Single ended: 50 OHMs (all signal layers)
    • Differential: 70, 90 and 100 OHMs (all signal layers)
  • Other requirements
    • Minimum through-hole VIA: 0.45mm (pad) / 0.2mm (drill)
    • Minimum track / clearance: 0.1 mm / 0.1 mm (more expensive PCB: 0.075mm / 0.075mm)
  • If uVIAs are used
    • uVIA: 0.25mm (pad) / 0.1mm (laser drilled hole)
    • buried VIA: 0.45mm (pad) / 0.2mm (drill)
I also found useful information about HDI stackups in this Mentor document: HDI Layer Stackups for Large Dense PCBs

HDI PCB technology comparison (picture from the Mentor document)
stackup_example