TUSB501-Q1: USB3.2 Redriver

Hi Yuto,

Yuto Kitamura said:

Q1: Do we have automotive grade USB3.2(10Gbps) redriver?
We do have 5Gbps for TUSB501-Q1, and 1:2 active MUX for TUSB1021-Q1, and  DP MUX sink/source for TUSB541/5461/1064/1164-Q1. Also we do have non-automotive grade TUSB1044A.

For automotive grade 10Gbps redrivers, the TUSB1021-Q1, TUSB1064-Q1, TUSB1146-Q1 are our only Q100 automotive grade 10Gbps parts. We do not have a Q100 grade part of the TUSB1044A.

Yuto Kitamura said:

Q2: For TUSB501-Q1, can we use it for SBU line of type-C especially for DP-Alt mode?
 1. If HPR2, the datarate/lane is 5.7Gbps/lane.
 2. If HBR3 is needed,  it will be 8.1Gbps/lane.

The AUX/SBU signals tend to maintain their signal integrity over longer cable lengths, as these signals tend to be a much lower bandwidth that signal data rates, typically acting at 1 to 2 Mbps. Rarely is a redriver needed, even at longer cable lengths. No redriver should be needed.

Yuto Kitamura said:

Q3: Do we also need redriver at CC1/2? If so would you plesae provide 

A redriver should not be needed for the CC pins either.

Going by the picture provided, I see that it says that a cable of length up to 5 meters may be used. For a USB3 10Gbps signal, the max cable length is 1 meter. We strongly recommend against a 5 meter cable for these higher data rates, as it will be very difficult for our redriver to fully compensate the amount of loss this cable will cause. I would recommend keeping the distance from the host to the redriver as minimal as possible.

Thanks,

Ryan

Hi Ryan,

Thanks for comments.

Let's assume the cable is shorter than 1m. Can we use TUSB541-Q1 for DP-HBR1.2(5.7Gbps/lane) redriver?

I understood, we do not need redriver for CC or SBU.

Hi Yuto,

The TUSB5461-Q1 should be able to support this application, yes. 

Thanks,

Ryan

Hi Ryan,

Isn't it TUSB564-Q1 or TUSB1064-Q1? TUSB5461-Q1 is for Source application. We are mainly targeting DP Sink application.

When we use those products for just redriver function, can we not use CTRL/FLIP pins for flip/dp mode control which means tied to fixed function?

Best regards,
Yuto

Hi Yuto,

For a sink application, yes the TUSB564-Q1 or TUSB1064-Q1 would be the correct device. I could not tell what application this was for, hence I said the TUSB5461-Q1. Just to confirm, this is a sink application then correct, i.e the signal enters from the type-C connector and the DP/USB lanes are split up at the redriver.

Yuto Kitamura said:

When we use those products for just redriver function, can we not use CTRL/FLIP pins for flip/dp mode control which means tied to fixed function?

The FLIP functionality is used to control the orientation of the mux based on the orientation of the type-C connector. Depending on how the cable is connected to the type-C connector, the TUSB564/1064-Q1 will need to be flipped to match this orientation.

If DP alt-mode functionality is being used, a PD controller is required. Typically, these CTL0/1 and FLIP pins can be controlled by the GPIO of the PD controller, or via I2C with the PD controller. I would recommend using these pins in conjunction with a PD controller.

Thanks,

Ryan

Hi Ryan,

Thanks for comments.
Let me go back to the system components.

There is dedicated DP MUX and PD controller at control board and flip, PD/CC negotiation are done here. For this MUX we can use TUSB1046 or TUSB546 with FLIP/CTLR pins controlled by PD controller.

What I want to discuss here is receptacle board redriver(surrounded by orange rectangle). It is only used to redrive the signal from Type-c receptacle to send the DP/USB3.x signal to control board placed around 1m away via cable. We do not need flip or other function, we just need redrive the signal.
In this case, is TUSB546 or TUSB1046 best solution from TI? If yes, can we not control FLIP/CTRL pins and can we use fix MUX configuration?

Best regards,
Yuto

Hi Yuto,

I understand, so the signal is being received by this receptacle board and essentially being passed though to the control board, so you want to boost the signal at this receptacle board, correct?

In that case, the TUSB1044A would be best for that use case, however this device does not have an automotive variant. Otherwise, the next best option would be the TUSB5/1064-Q1, however this wouldn't be a perfect fit.

One question I have, is this being used for purely DP, or is this being used for a 2-lane DP 2-lane USB3 application? If only DP is being used, then the 5/1064-Q1 would fit well here still.

Thanks,

Ryan