SPRAAR7J November   2018  – February 2023 66AK2G12 , AM1806 , AM1808 , AM2431 , AM2432 , AM2434 , AM3351 , AM3352 , AM3354 , AM3356 , AM3357 , AM3358 , AM3358-EP , AM3359 , AM3871 , AM3874 , AM3892 , AM3894 , AM4376 , AM4377 , AM4378 , AM4379 , AM5706 , AM5708 , AM5716 , AM5718 , AM5726 , AM5728 , AM5729 , AM5746 , AM5748 , AM5749 , AM620-Q1 , AM623 , AM625 , AM625-Q1 , AM625SIP , AM62A3 , AM62A3-Q1 , AM62A7 , AM62A7-Q1 , AM62P , AM62P-Q1 , AM6411 , AM6412 , AM6421 , AM6422 , AM6441 , AM6442 , AM6526 , AM6528 , AM6546 , AM6548 , BQ24392-Q1 , HD3SS6126 , LP8727 , OMAP-L137 , OMAP5912 , TMS320C6745 , TMS320DM335 , TMS320DM355 , TMS320DM365 , TMS320DM368 , TMS320DM369 , TMS320DM6441 , TMS320DM6443 , TMS320DM6446 , TMS320DM6467 , TMS320DM8127 , TMS320DM8147 , TMS320DM8148 , TMS320DM8165 , TMS320DM8167 , TMS320DM8168 , TMS320VC5506 , TMS320VC5507 , TMS320VC5509A , TS3USB221A-Q1 , TS3USBA225 , TSU5611 , TSU6111 , TSU6111A , TSU6721 , TSU8111

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
    1. 1.1 Scope
    2. 1.2 Critical Signals
  4. 2General High-Speed Signal Routing
    1. 2.1 PCB Fiber Weave Mitigation
    2. 2.2 High-Speed Signal Trace Lengths
    3. 2.3 High-Speed Signal Trace Length Matching
    4. 2.4 High-Speed Signal Reference Planes
  5. 3High-Speed Differential Signal Routing
    1. 3.1  Differential Signal Spacing
    2. 3.2  High-Speed Differential Signal Rules
    3. 3.3  Symmetry in the Differential Pairs
    4. 3.4  Crosstalk Between the Differential Signal Pairs
    5. 3.5  Connectors and Receptacles
    6. 3.6  Via Discontinuity Mitigation
    7. 3.7  Back-Drill Stubs
    8. 3.8  Increase Via Anti-Pad Diameter
    9. 3.9  Equalize Via Count
    10. 3.10 Surface-Mount Device Pad Discontinuity Mitigation
    11. 3.11 Signal Bending
    12. 3.12 Suggested PCB Stackups
    13. 3.13 ESD/EMI Considerations
    14. 3.14 ESD/EMI Layout Rules
  6. 4References
  7.   A Device Layout Parameters
  8.   Revision History

Connectors and Receptacles

When implementing a through-hole receptacle (like a USB Standard-A), TI recommends making high-speed differential signal connections to the receptacle on the bottom layer of the PCB. Making these connections on the bottom layer of the PCB prevents the through-hole pin from acting as a stub in the transmission path. For surface-mount receptacles such as USB Micro-B and Micro-AB, make high-speed differential signal connections on the top layer. Making these connections on the top layer eliminates the need for vias in the transmission path. For examples of USB through-hole receptacle connections, see #SPRAAR72795.

GUID-C69C6290-0AAD-4428-8C21-947F117ABDF2-low.gif Figure 3-4 USB Through-Hole Receptacle Connection