TPS65987D: Fault event & USB3.2 Gen2 connect

Hi Hiroshi, 

Thank you for reaching out!

I will look into this and get back to you by EOB Monday 3/27/23.

Best Regards,

Aya 

Thank you for your response.
I look forward to your reply.

Hi Hiroshi, 

Thank you for your patience. 

1. The FaultZ Output event is asserted low meaning that it would be active H when nothing is happening and low during an overcurrent event. I understand that you have that inverted in the GUI so the behavior is the opposite. The concern is why there is an overcurrent event when connecting the device. Try selecting " Open Drain Output Enable" to see if this fixes the issue. 

2. Could you please clarify your method here? Are you using debug mode to see if USB 3.0 is detected or maybe a PD analyzer? Also do you mean USB 2.0? 

Best Regards,

Aya 

Hi Aya-san,

As a result, there was no improvement.

1. I checked with normal settings, but there was no change.
I also changed the setting to OpenDrain, but there was no change.
Here, I monitored R172 (no 0Ω resistor implemented) GPIO2 on the TPS65988EVM, and it is also asserted low.

For example, does overcurrent detection due to start-up current during board power-up affect this issue?
Normally, after the power is turned on, the RAM data is loaded from the SPIFlash and this IC becomes effective after the configuration, so I don't think it will be affected when the power is turned on.
Also, is there a parameter (set value) that determines overcurrent detection somewhere?

2. Confirming the device information connected via USB on a Windows or Linux computer.
For Windows, free display software is used.

Even if a SanDisk SSD (USB3.2 Gen2) is connected, the USB Version will be 2.1 as shown above.

If not through EVM, it will be recognized by 3.2Gen2 normally as shown below.

On a Linux machine, you can check the connection with the lsusb command, but it is a USB2 connection.

Additional Information
The following three GPIOs are wired from TPS66587 to TUSB546,
Since GPIO6, which indicates USB3 connection, is not activated, the TPS66587 does not recognize it as USB3 in the first place.

When the aforementioned SSD is connected, it becomes active for a moment and the LED lights up (for about a few seconds), but it goes off immediately.
Is it canceled even though it was recognized for a moment?

Best regards,

Hiroshi

Hi Hiroshi-san, 

Thank you for your feedback. I will look into this further and get back to you by mid-next week. 

Best Regards, 

Aya 

Hi Hiroshi-san, 

Thank you for your patience. 

I notice that you seem to use both the TPS65987DDH and the TPS65988. Each device has different GPIO configurations, so there may be inconsistences between the two. 

1- Yes there is a parameter to set the overcurrent protection in the GUI. You can change the 'Peak Current' percentage in Transmit source/sink capabilities.

2- I would highly recommend reading into the Data Status register in debug mode to see which USB speed the PD is recognizing (see image below).

Could you please do this and let me know the results you find? 

Best Regards,

Aya 

Hi Aya-san,

Thank you for answer.

Finally, It was improved by checking the following USB Capable.

Please tell me one last thing.
　What does "USB capable" enable?
　TPS65987DDH and TPS65988DH Host Interface Technical Reference Manual (Rev. B), P40, TX Source Capabilities Register Bit
　Byte12 changed from 0x01 to 0x05.
　It says First Source Capabilities PDO contents Bank 0. What signal is assigned?

Even if this setting was reflected on our board, USB3 was not enabled, but when the TPS65987 detected OverCurrent, the OS restricted the USB speed.
After disconnecting the OverCurrent interrupt signal and checking the connection, it was recognized as USB3.

About Over Current issue,
By changing "Initial Value" from 0x0 to 0x1, low assertion at startup has been improved.

Best regards,
Hiroshi

Hi Hiroshi-san, 

I am happy to hear that there is improvement. I am going to look into those settings and let you know by EOB Monday. 

Best Regards, 

Aya