SLLSE76Q March 2011 – March 2024 TUSB7320 , TUSB7340
PRODUCTION DATA
The high-speed differential pair (USB_DM and USB_DP) is connected to a type A USB connecter. The differential pair traces should be routed with 90 Ω ±15% differential impedance. The high-speed signal pair should be trace length matched. Maximum trace length mismatch between high speed USB signal pairs should be no greater than 150 mils. Keep total trace length to a minimum, if routing longer than six inches contact TI to address signal integrity concerns. Route differential traces first.
Route the differential pairs on the top or bottom layers with the minimum amount of vias possible. No termination or coupling caps are required. If a common mode choke is required then place the choke as close as possible to the USB connector signal pins. Likewise ESD clamps should also be placed as close as possible to the USB connector signal pins (closer than the choke).
For more detailed information, you may also see the USB 2.0 Board Design and Layout Guidelines which describes general PCB design and layout guidelines for the USB 2.0 differential pair (DP/DM).