TUSB8041: Connect TPS2561

Hi,

What is your configuration of FULLPWRMGMTz/SMBA1/SS_UP? Are you asking if you should install a pull-up resistor to this connection or connect them directly?

Hi Malik.
Currently, It was direct connect between EN pin of the TPS2561 and PWRCTRL1_BATEN1 of the TUSB8041.
I will disconnect.
And, I want to design that it always is pull-up EN pin of TPS2561.
If the TPS2561's EN pin design pull-up, could this cause problems with the USB system?

Thank you

Hi Charles,

Are you enabling full power management through the FULLPWRMGMTz/ SMBA1/SS_UP pin? If so then a direct connection between EN pin of the TPS2561 and PWRCTRL1_BATEN1 of the TUSB8041 is correct. Is this a Type-A or Type-C application? If Type-C Vbus cannot be present before CC detect to the UFP. What are you trying to achieve in your application? Are you looking for some sort of constant charging mode?

Dear Malik.

Are you saying that "USB Host can also send Port_Power On / Off" is the protocol defined in USB communication?
The customer wants to make sure that "USB Host can also send Port_Power On / Off" is a normal sequence by USB communication protocol.
So, the customer wants more information about it.

The customer has the following problems.
In the system using TUSB8041 + TPS2561, the above-mentioned waveform causes the problem that the boot loader is not uploaded correctly because of the USB recognition is lost during the initial boot.
(The FULLPWRMGMTz / SMBA1 / SS_UP pin is floating.)
In order to solve this problem, they are also reviewing the EN pin of the TPS2561 is always High.

Hi,

More information on the the USB PORT_POWER command can be found int he USB specification. When you say initial boot are you referring to TUSB8041 power reset? Is there a schematic that can be reviewed?

Hi

The situation in question is as follows.

  - When resetting the PC, the EN pin of TPS2561 becomes high to low.

  - Because the EN of TPS2561 is changed, the PC cannot read the USB data from the start of the boot.

The customer does not want to control the power supply.

The customer wants to construct the circuit as follows:

1. Disconnect the EN pin of TPS2561 and PWRCTRL1_BATEN1 of TUSB8041.

2. Always enter the High signal on the EN of TPS2561.

Is there a problem with USB communication (system) when changing the circuit as above?

Attached is the current circuit diagram.

Please review.

USB_SCH.pptx

Hi,

Sorry for the delayed response. Enabling the switch at all times or keeping Vbus active at all times is okay if you are not enabling DCP charging features on the downstream port.

Hi Malik
If Vbus always keeps turn-on, when over current occur of Vbus, is it no problem?

Hi Charles,

Could you give more detail to your question? In what case? For USB compliance the USB Hub should be able to report over-current events. Are you referring to this feature of the USB Hub in your implementation? If over current reporting is not used the OVRCUR pin on the specific port should be pulled high.