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TPS65987D: Controlling a TUSB1046 SS Mux

Part Number: TPS65987D
Other Parts Discussed in Thread: TUSB1064,

Hello there,

I intend to use a TPS65987D to control a TUSB1064 Mux. The TUSB1064 output signals are used in a HUB circuit (TUSB8044) and in a TUSB1046. I need to make sure that the TUSB1064 never enters the configuration in which the RX/TX inputs are "directed" only to the TUSB1046, as follows: 

As it can be seen in the TUSB1064 datasheet, when operating in the GPIO Configuration Mode, the selection signal CTL0 been pulled High would mean that it would never enter this state. Can I simply pull the CTL0 pin to High, to make sure it never "bypasses" the HUB? If not, then how could I make sure it never enters this configuration? Also, is there a similar solution to this problem if I decide to use the TUSB1064 in the I²C configuration Mode?

Thanks,

Eduardo Alves

  • Hi Eduardo,

    The TPS65987D has a GPIO configuration option to "Enable without event" this would allow for the GPIO signal to always be high when the PD controller is booted. We just released a new application note highlighting all of the GPIO events the TPS65987D offers, you can refer to it here:

    If this answers your question, PLEASE select This resolved my issue

    Thank you,

    Eric

  • Hello Eric,

    I'm going to take a look at it.

    Besides this, I have another question: Is the DisplayPort Alt Mode enabled by default in the TPS65987D, or do I need to configure it manually via firmware? I'm asking this because of the HPD signal.

    Thank you,
    Eduardo
  • Hi Eduardo,

    You can look at the default ROM configurations of the TPS65987D from the datasheet by adjusting the resistor divider on ADCIN1. One of those configurations should meet your needs. If not, you could use the TPS6598x Application Customization Tool to configure the device exactly to fit your application.

    Thank you,
    Eric
  • Hello Eric,

    Thank you for your reply.

    There is no configuration in the datasheet which enables the DisplayPort Alt Mode. This means I would have to enable it via firmware, correctly?

    In this case, how can I configure the firmware of this chip? I couldn't find in the documents any reference to programming the chip without the TPS6598x-EVM, but I don't have this module, and it looks to me that there must be a simple way to do it, maybe with a TM4C1294  microcontroller (or perhaps something simpler). 

    Thank you,

    Eduardo

  • Hi Eduardo,

    You can use the TPS6598x Application Customization Tool to create your configuration image and then use either an embedded controller or an external SPI Flash to push that configuration onto the TPS65987D during bootup. The easiest option would be to add an external SPI Flash onto your board like in the TPS65987EVM.

    You can download the configuration tool here:

    and here is the user's guide for the configuration tool:

    If this answers your question, PLEASE select This resolved my issue

    Thank you,

    Eric