TI USB Hubs: Adjusting USB_R1
TUSB8020B, TUSB8041, TUSB8042, TUSB8043 and TUSB8044 are all USB-IF compliant USB 3.x hubs. They provide simultaneous SuperSpeed and High-speed connections on the upstream port and provide SuperSpeed, High-speed, Full-speed or Low-speed connections on the downstream ports. TUSB4041I and TUSB4020BI are a USB-IF compliant USB 2.0 hubs. They provide High-speed connection on the upstream port and provide High-speed, Full-speed or Low-speed connections on the downstream ports. This document describes and demonstrates the effects of adjusting the pull down resistor on USB_R1 ranging from a max of 10.85- kΩ ±1% to 8.25-kΩ ±1%, with a recommended value of 9.53-kΩ ±1%.