• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Subscribers 63 subscribers
  • Views 221 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPS65988DK: Configuring a USB-C/PD Controller for a Type-A Output

Perry Watson
Prodigy 30 points
Part Number: TPS65988DK
Other Parts Discussed in Thread: TPS2546, TPS2547, TPS2514A, TPS65987DDK

I'm working on a new USB charging product to be installed on airplanes. I understand the power requirements well enough: it has to take 12V-32V input and be able to provide up to 45W of power per output with >95% efficiency. I'm looking into a GaN FET buck converter for that part.

What I really need help with is understanding which USB controller IC to use. We want to be able to have a USB-C only option, and an option with USB-C and USB-A. Maybe a dual USB-C output option as well.

While researching this, I found the reference design PMP40543, which uses the same nominally USB-C controller chip for both the USB-C and the USB-A output.

The idea of using a USB-C controller for the USB-A output appeals to me because it would allow me to use a dual-port USB-C controller, like the TPS65988DK, for both the USB-C and USB-A outputs simultaneously.

What are the requirements and restrictions when configuring a USB-C controller IC for a USB-A output? Could the TPS65988DK be configured for one USB-C output and one USB-A output? I need to understand what we can and can't do to make an informed decision for the direction of this project.

If anyone can provide insight into this aspect of USB charger design, I would greatly appreciate it. Thank you.

  • 0
    TI__Expert 8470 points

    Hi Perry,

    The TPS65988DK is not designed to act as a type-A source but may be able to with some adjustments. We do not recommend doing this as this is not a tested function of the TPS65988DK.

    Are you planning to use BC1.2 with the type-A source output port? 

    The adjustment you would have to make is to the CC pins of the TPS65988DK. Since type-A ports do not use CC lines, you would need to permanently pull the CC pins of Port A/B (whichever you decide to use for type-A) on the TPS65988DK low to ground through a resistor to force an always on 5V VBUS output as required for type-A sourcing.

    Best,

    Alex

  • 0 in reply to Alex Liu
    Prodigy 30 points

    Alex,

    If I could find a chip that could do the BC1.2 with the type-A source output, that would be ideal. In truth, I don't know what all of our options are for a type-A output. I know that type-A is not always limited to just 5V output, as I found a wall adapter with a type-A output that can provide 5V 3A, 9V 2A, or 12V 1.5A.

    What I really need is to find a way to control the output of a type-A USB port that provides as much charging capability as possible without the risk of damaging someone's phone or other device.

    It sounds like the TPS65988DK is not what I'm looking for. How can I know if an IC is capable to controlling a type-A port in this way?

    Thank you,

    Perry

  • +1 in reply to Perry Watson
    TI__Expert 8470 points

    Hi Perry,

    Any devices that offer quick charging capability above 5V 1.5A on USB Type-A are in violation of the USB Type-C spec from USB-IF. I know some device designers/manufacturers will have their own proprietary technology to enable this, but it is outside of USB specifications. TI does not offer any USB controller ICs that are compatible with providing greater than 5V 3A on a Type-A port. All of TI's solutions follow the USB spec. For BC1.2, I believe the max output defined by USB BC1.2 spec is 7.5W.

    That being said, we do offer USB Type-A BC1.2 controller/power switches. The TPS2546 or TPS2547 could work for your application. These are USB charging port controllers, compatible with type-A, and they have built in power switches for the power path as well as load detection. The TPS2514A is another BC1.2 solution compatible with USB Type-A. This solution does not have built in power switches for the power path, so you would need an external power switch should you choose not to leave the VBUS supply at the port hot. These are all available on ti.com.

    https://www.ti.com/product/TPS2546

    https://www.ti.com/product/TPS2547

    https://www.ti.com/product/TPS2514A

    From what I have understood, you are looking for a BC1.2 charging port controller. Any IC that offers BC1.2 control should work, given you have a 5V supply and you are routing the connections from the pins of the IC to the Type-A port. For the other USB Type-C port you mentioned, a single port PD controller such as the TPS65987DDK would work for you. This PD controller can control power output up to 20V 5A.

    Best,

    Alex

  • 0 in reply to Alex Liu
    Prodigy 30 points

    Alright, thanks for the help. I think I have what I need, now.