SNAA408 April   2025 LMK3H0102

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Output Recommendations
    1. 2.1 Differential vs. Single-Ended
    2. 2.2 Slew Rate
    3. 2.3 Spread Spectrum Clocking
  6. 3PCB Design
    1. 3.1 Stackup
    2. 3.2 Power Filtering
    3. 3.3 Avoid Bottlenecking
    4. 3.4 Strategic Via Placements
      1. 3.4.1 Distributing Power Concentrations
        1. 3.4.1.1 Via Sizes
        2. 3.4.1.2 Pads and Pours
      2. 3.4.2 Shielding and Stitching Vias
  7. 4Minimize Possible Antennas
    1. 4.1 Stubs
    2. 4.2 Net Pours
  8. 5Summary
  9. 6References

5 Summary

PCB layout is one of the main contributors to EMI performance of a system. When designing a board, this is crucial to maintain a clean power supply (via capacitors and ferrite beads) and a strong ground (via additional ground vias). The PCB layer stackup and trace layout can also be optimized for additional ground shielding and smooth power flow.

When using clocking devices, different settings, such as SSC, can be used to reduce EMI emissions further.