TPS23861: The technology issue for TPS23861

Hello Zhang,

Thank you for reaching out. I have a few follow up questions:

1. Can you please clarify what you mean by "control to close a certain route separately." Are you referring to separating the SDA and SCL signals on the I2C bus? 

2. If using another device, such as a router, along with the TPS23861 and a difference in ground potential is not a concern, the two I2C signals do not have to be separated as both devices have different slave addresses for communication. 

3. If you are looking to separate the signals due to a grounding concern, please use a bidirectional I2C isolator. TI's ISO1640 is a possible solution for isolating the grounds for TPS23861 and the MCU being used. The LSI1012LT1G being used in your current design will only separate the signal unidirectionally, which will not work for I2C communication. 

ISO1640 Datasheet: ISO164x Hot-Swappable Bidirectional I2C Isolators with Enhanced EMC and GPIOs datasheet (Rev. D)

Thanks,

Anagha 

Hi Anagha,

Thanks for you kindly support.

Sorry for my unclear description, TPS23861 has the Quad Port PSE, and we want to control one of the Quad Port PSE to turn on/off, 

so we want to know if the I2C can configure the request or not, and how to Implement this function?

Anagha Jagannath said:

3. If you are looking to separate the signals due to a grounding concern, please use a bidirectional I2C isolator. TI's ISO1640 is a possible solution for isolating the grounds for TPS23861 and the MCU being used. The LSI1012LT1G being used in your current design will only separate the signal unidirectionally, which will not work for I2C communication. 

We will modify our design from LSI1012LT1G to ISO1640 because of the idirectionally, is there any other error for our design? thanks.

Hi Zhang,

Thanks for clarifying. From my understanding, I2C does not need to be used to turn one of the Quad Ports on/off. Here are two ways that a single port can be turned on/off:

1. Firstly - if you are looking to use only one of the PSE's four ports in your design, the remaining ports can be left unused. To implement this, ground the unused SEN pins and leave the unused GATE pins floating. Please refer to section 8.2.2 - Connections on Unused Ports in the TPS23861 Datasheet for further information about this. 

2. Another way to configure one port to be on/off if all four ports are being used in the design is to configure the Operating Mode Register (0x12). There are four operating modes the port can be configured to which include Off, Manual, Semi-Auto, and Auto. 

The rest of the design looks good in the screenshot you attached above. Feel free to send us the full schematic for review if you would like. 

Best,

Anagha