TUSB8041: any additional settings to test eye diagram

Lijia Zhu

Part Number: TUSB8041

Hi team,

my customer is testing eye diagram of USB2.0 stream. We can get the signal at the USB_UP side, but can't see any signal at output at the USB_DN side. Any additional settings to let the signal pass the chip?

B&R

Lijia

over 4 years ago

+1 JMMN over 4 years ago

TI__Guru 60870 points

Hi Lijia,

The hub doesn't pass the USB 2.0 test packet, each downstream port will generate its own test packet for the test. Using the XHCI HSETT tool from the USB-IF (usb.org) you can send the command to the hub for it to enable downstream test packets on a particular port.

https://e2e.ti.com/support/interface-group/interface/f/interface-forum/1031982/faq-tusb8041-tusb8041-how-do-i-force-a-usb-hub-to-send-usb-2-0-high-speed-test-packets-for-eye-diagram-testing

If the eye diagram needs to be adjusted see this app note:

https://www.ti.com/lit/an/slla429/slla429.pdf

Regards,

JMMN

Interface

Interface forum

TUSB8041: any additional settings to test eye diagram