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TPS65987D: TPS65987+TPS55288

Part Number: TPS65987D
Other Parts Discussed in Thread: TPS55288EVM-045, TPS65987EVM, TPS55288, USB-C-PD-DUO-EVM


I have:

TPS65987EVM + TPS55288EVM-045

I having a hard time trying to the TPS65987 to send i2c command to TPS55288, i even followed the "" but no luck, can some help me and provide step by step?


  • Hi Allen,

    You should see this app note for the I2C Master settings:

    From your project file, it looks like there are no I2C Master Events inputted, you can see these by, clicking Settings --> Show I2C Master Events Table. You will need to input the data you would like the PD controller to send to the other device.

    Also, in 0x62, I noticed that you put in number of indices and start index under Port 1, please move these to "Common."

    Thank you,


  • 2746.test.pjt

    power sink, is there documents that has example of setting up power sink? use apple macbook power supply to extract 20v power? (or any other rail?)  i dont think i did it right, here is updated config file

  • Hi Allen,

    Yes it looks like you have both ports configured for I2C master and also on Port Control register you have chosen to initiate/process source capabilities but will need to change to sink if you would like the PD controller to be just sink only. 

    Also, is this the updated project file? I still don't see any I2C Master Events inputted.

    I would recommend watching these tutorials on the product page to help configure the device:

    Thank you,


  • 1) i need to do both sink and source
    2) where/i dont see  I2C Master Events in the program?
    3) where is the GUI PD log in the program?

  • Hi Allen,

    To do both, you will need to select both process swap to source and sink and deselect both the Initiate swap for source and sink.

    I mentioned in my previous reply for the I2C Master Events, you will need to go to Settings --> Show I2C Master Events Table.

    I'm not sure I understand your last question, are you asking how you can capture PD logs? If so, you will need a PD analyzer such as one from Total Phase.

    Thank you,


  • -> there is no "Show I2C Master Events Table", there is only "Show I2C Control Events Table"

    -> you will need to select both process swap to source and sink and deselect both the Initiate swap for source and sink.

    is this correct?

    here is the updated config file with change


  • related question, i am using

    USB-C-PD-DUO-EVM Evaluation board

    for testing, 

    i am connecting the source to sink directly with type-c cable and apply power supply to the sink board, however,  the sink 9v 15v 20v button does not respond, does that mean there is issue with onboard (sink) firmware? if so, can i have the default firmware to relish it? 

    only place i found in the application is :

    also i already split the USB-C-PD-DUO-EVM to 2 separate board, and in order to flash sink board, i stack on top of each other and set jumper to SNK

    however, if i use the following: Device > Re-Flash EVM Firmware (Recovery) > and select "tps65987_power_duo_mode_SINK_EVM_flash_image.bin" i get error/SPI error, eventho the setting shows SPI is working fine

  • Hi Allen,

    Yes that's the correct I2C Events option and the Port Control looks good.

    For the default firmware, yes that looks correct and you will be able to flash those project settings. For programming the different boards, I believe there's a jumper to select which board. 

    To negotiate the other voltages on the sink side, you first have to push the corresponding buttons on the Source board, this will update the Source capabilities of the board and then on the Sink side, when you press the same button for the voltage you selected on the source board, it will negotiate to that afterwards.

    I would recommend taking a look here, please refer to this video: USB-C-PD-DUO EVM Video

    Thank you,