Hi TI Team,
We will use TUSB564-Q1 in our new Program,and will use the internal Mux of TUSB564-Q1,can we keep the SBU1 and SBU2 unconnected with PD controller?
If control TUSB564-Q1 by GPIO Mode,will AUX Snooping be disable by default?
Thanks!
Hi,
We will use TUSB564-Q1 in our new Program,and will use the internal Mux of TUSB564-Q1,can we keep the SBU1 and SBU2 unconnected with PD controller?
The purpose of only connecting AUX/SBU through one of the devices is so the signal will not be double flipped. The PD controller and the TUSB564-Q1 both may have a AUX/SBU mux internally. If the signal is routed through both, then the signal will be MUXed twice resulting in no chnage in the flip orientation.
This is why its best to route though either the PD controller or the TUSB564-Q1
If control TUSB564-Q1 by GPIO Mode,will AUX Snooping be disable by default?
Yes, this is correct:
Hi Vishesh Pithadiya,
Thanks for your information.
When we design the TUSB564 schematic like below function Diagram, the AUX Channel didn't work.
But when modify the schematic to below function block diagram, remove the 0ohm between TUSB564 and DP-IN Sink, and connect the AUX+/AUX-(DP-IN Sink) to SBU1/SBU2(Type-C1 DP-IN Source) directly(SBU1 and SBU2 are still connected to TUSB564), the AUX Channel works and the DP Function is ok.
Could you please help to check why these happened? Did we misconfigure some pins？
Base on the above schematic, we measure some waveforms for your reference.
AUX+(DP-IN Sink Side)
AUX-(DP-IN Sink Side)
AUX+_IC (TUSB564 Side)
AUX-_IC (TUSB564 Side)
Thank you very much!
Hi,
In your system there are two USB Type-C connectors. In this case you will need two Muxes and two CC controllers.
For an application like this you need a system like this:
Hi,
Understood, looks like the second USB Type-C connector will be fixed in orientation. I would test this in the following order:
1) Is flip being set correctly. (use a DMM to probe the flip pin of the TUSB564-Q1 and make sure that its set appropriately)
2) Is the AUX/ SBU mux operating correctly. Use a continuity tester to see if the MUX is routing the signals as defined by the datasheet.
3) Try testing all orientation of the input USB Type-C cable to see if any orientation works.
Hi,
1) Is flip being set correctly.---Yes, the flip is being set correctly.
2) Is the AUX/ SBU mux operating correctly
Test result shown as below:
It seems the AUX/ SBU mux is not operating correctly.
Test Setup:
Test result:
3) Try testing all orientation of the input USB Type-C cable to see if any orientation works.
---No orientation works.
Thanks！
Hi,
Are you able to share an aux log of the working and non working case?
When were the PUP and PDOWN added?
These are not required here, as this part between the source and sink.
The 100K PUP and PDOWN should be present on the source on the other side of the Type-C1 connector.
The 1M PUP and PDOWN should be present on the sink side of the Type-C2 connector.
Hi,
The set up (pull up/pull down 100kohm) is just for testing the voltage of SBU/AUX.As you can see, I also remove the DP source and DP sink.
When I check the DP function, I will remove the 100kohm.
We don't have a tool to capture the log.
Why the voltage of Aux+ is about 1.75V and Aux- is about 0.79V when the Flip pin is 0V ?
Thanks.
Hi,
Why the voltage of Aux+ is about 1.75V and Aux- is about 0.79V when the Flip pin is 0V ?
I agree that these measured voltages are incorrect.
The end to end DP AUX path should look as follows:
The common mode voltage should be the result of the voltage divider network created by the PUP and PDOWN resistors,
In our case the DP source will have the 100K PUP and PDOWN, the sink should have the 1M PUP and PDOWN.
When the source and sink are connected, the common mode voltage should be close to:
AUXp: 0.3V
AUXn: 3.0V
I'm not sure what is causing the voltage to drop to 1.755V and 0.792V. Is there anything else connected on this path?
Try doing an ABA swap with the TUSB564-Q1 to see if the issue follows the part.
