TUSB522P: TUSB522P_Rx_5G_Comp-Fail, it can’t enter loopback

Every_Hsiao

Can you please share their schematic and layout for review? 

Are they fully passing the TX compliance? 

The external instrument (M8000) enters from the RX -> Do they have AC coupling caps on the board? If not, are they adding external 0.1uF caps?

Thanks
David

HI David,

Sure, how to share the schematic and layout with you?

TX test does not need Loopback, directly connected to the fixture test.

I afraid we can not adjust the the components on the external instrument (M8000).

/Every_Hsiao

/Every_Hsiao

Can you please accept my friendship request so you can send me the schematic and layout in a private message?

Do you have AC coupling on the RX? If not, then you need to add the AC coupling capacitor externally as shown in the diagram below.

Thanks

David

Do you have AC coupling on the RX?

=> Yes, the test team has AC coupling on the RX.

May I have your mail address?

I can't upload the layout file because the size is larger than 68M.

/Every_Hsiao

/Every_Hsiao

With input trace of 12.6in, which is around 7dB loss, and output trace of 8.5in, which is around 5dB loss, I would make the following change

EQ1 = Mid -> 6dB. 

DE1 = Floating (3.5dB) or High (6dB)

EQ2 = Low (3dB) or Floating (6dB)

DE2 = High (6dB)

Have you ran the TX compliance first and is it passing?

Thanks

David

Currently, the setting as following.

1. OS1 / OS2: LOW=>High,TX Fail, Rx_5G_Comp-Fail  Can’t enter loopback
2. DE1 / DE2: LOW=>Floating,TX PASS, Rx_5G_Comp-Fail  Can’t enter loopback
3. DE2: Floating => High, Rx_5G_Comp-Fail  Can’t enter loopback
4. EQ2: LOW=>Floating

Have you ran the TX compliance first and is it passing?

Every: TX can pass after adjust DE1: LOW=>Floating

/Every_Hsiao

Every_Hsiao

For the RX JTOL, did you try to put the PCH (USB Host) into compliance mode and see if it can enter into loopback?

If it still does not work, is it possible you can send the system to me?

Thanks

David

Please see the two comments from Intel

1. A 3rd party vendor will perform the SI/EV for compliance testing. In that case, you do not need to enable compliance mode for USB electrical certification on EBG. The 3rd party certification test house will be able to put the USB port in the correct mode for testing.

2. This CScripts function is for PCH USB port BIOS setting checking, not for re-driver.
Per phone discuss, your platform can work at compliance normally without re-driver. That means BIOS is working correctly so this CScripts function may not help on this question.
Since BIOS is setting correct, if there have any issue when using re-driver please contact re-driver vendor for further analyze.

Currently, we still can't into compliance mode and enter into loopback.

Could you please contact us to fix this issue?

Hi,

It will still help if you can enable the compliance mode for PCH. 

On the Keysight M8000, there are different link training script, can you try different scripts and see if they help?

Any chance you can work with our local office and send a system to me?

Thanks

David 

HI David,

Could you please suggest the suitable scripts for testing?

I can contact who to fix this issue? It;s hard to send a entire system to me, it's too large.

I hope that your FAE can go to the lab in Taipei office and let's test this Rx loopback issue directly.

Please contact me ASAP, it's gating item to GBO now.

 Every_Hsiao

Office: +886 2 2658 6288 EXT 53034

Mail address: Every_Hsiao@compal.com

COMPAL ELECTRONICS, INC.

Every_Hsiao

I reached out to my local FAE and asked him to get in touch with you directly regarding this issue.

Thanks

David

HI David,

We can enter compliance mode through PCH to internal USB.

However, through USB 3.0 re-driver(TUSB522PRGET) no matter how to adjust the control PIN Setting, we still can’t enter compliance mode.

Thank you.

Every_Hsiao.

Every_Hsiao

You only need to put the particular port of the PCH into compliance mode. You do not need to put the redriver into compliance mode. Are you able to get into loopback with the port of the PCH in compliance mode?

Thanks

David

HI David,

We can't enter Rx_5G_Comp- loopback mode on JP73 USB3.

The others USB port can test successfully.

HI David,

I still don't receive the message from your FAE.

May I know who I can contact to debug this issue?

Thank you..

Hi, Every_Hsiao

I think Evan our FAE has already reached out to you for support on this issue?

Thanks

David