TPS65988: Design and solution question regarding USBC data and power hubs

Hi Asaf,

Unfortunately I primarily support the USB-C PD products (like the TPS65988) and may not be able to help you too much on the other parts.

For the "external Type-C port", if you are only using USB3 data speeds, you could use something like the TPS25751 to manage the port power and data. It supports up to 100-W Sourcing and SInking, and supports USB2 and USB3 speeds for data speeds.

Regarding your hub question, I will redirect this thread to a team that may be able to provide more help.

I would recommend submitting another E2E thread with a specific BMS ic mentioned to get a direct response from them regarding the BMS suggestion.

Thanks and Regards,

Chris

Hi Christopher!
Thank you for the answer!

I apologize, I'm just starting to learn TI's portfolio for USB-C solutions.

Could you clarify if the products dealing with USB-C data and the products dealing with USB-C power (PD) are two separate products? Is there a product dealing with both power and data for a USB-C interface?

Specifically, I'm looking for a 'USB-Data-and-Power Hub', of sorts, where on the one end an external device- power only/power and USB2 data/power and USB3.x data/power and USB-C data may be connected to my USB-C port. And on the other hand, two internal components may be connected- one via a USB-C connection (USB-C port using USB-C PD and data speeds) and one via a USB2 connection which will likely use a 4pin connection to the VBUS, GND, D- and D+ pads or a degraded USBC plug.

I'll continue going over TIs' videos and guides, perhaps I'll answer my own question

Thanks again!

Hi Asaf,

Asaf Pipman said:

Could you clarify if the products dealing with USB-C data and the products dealing with USB-C power (PD) are two separate products? Is there a product dealing with both power and data for a USB-C interface?

USB-C PD devices will advertise and negotiate the USB-C port Data and power contract, but does not actively do anything with the data. Regarding data, for example, it can negotiate DFP vs UFP, and also enter specific data modes on the port (USB, DP, TBT). For power, it also negotiates power roles (sink, source) as well as the power level of the port. TI's PD controllers also provide control for a Power Path switch controlling the power from the type-c connector to the system.

The PD can negotiate "max power", but you will need another power stage to actually manage the power going to the other devices.

These products do not do any USB muxing or act as a USB hub, and do not manage multiple internal streams of USB data. The PD devices simply advertise the Data capabilities and help negotiate direction (DFP/UFP). A usb hub would need to be a separate IC here, but I'm not too sure of the specifics of these devices and requirements.

Thanks and Regards,

Chris

Hi  Asaf:

     For USB hub, we recommend TUSB8042A, hub upstream port can be configured as UFP, hub downstream port can be configured as DFP , you also need USb3 mux like HD3SS3212 to handle USB-C flipping.

Best

Brian

Hi Brian!
Thank you very much, I'll look into those.
Two questions if I may:
1. I'm concerned with what I think is a simultaneous dual role my tablet would to occupy in the USB scheme I had specified above. I think the tablet will take the host role on the client-module to tablet connection while simultaneously taking the role of client on the external PC to tablet connection. Is this something a DRD port is able to do?
Another possibility is since both the external PC port and the tablet port are DRD, they could negotiate the tablet as host and the PC as client, I assume. Can this last point be held while the external PC is acting as a power source and the tablet as a power sink?
Does this negotiation require any intervention on my part or is this automatic?

2. If I were to drop the high data speed demand, and keep all data requirements to the USB2 level, I guess I would not need the HD3SS3212, since the TX and RX lines will not be relevant anymore. Will the USB hub choice change as well? Power requirements would still remain valid.

Hi again!
Browsing around I came across this TIDA-03027, which seems to fulfill my requirements, but is no longer available under TI.
It has bidirectional PD power connection from USB-C to USB-C ports, a USB2 output port which will provide 5V via the USB2 pins and USB HUB which will handle USB streams. I will not use the HDMI port.
Is there a similar product available?

Hi Asif:

   TI hub can not be configured as DRP ( dual role).

   If you only need USB2, then HD3SS3212 is not needed.

   for TIDA-03027, Maybe we can ask Chris.

Best

Brian

Hi Asif,

I found this thread regarding that design: https://e2e.ti.com/support/interface-group/interface/f/interface-forum/937655/tps65983b-is-tida-03027-still-available

I'm not familiar at all with the design and could not find to much resources pointing to it, but it seems like it uses the TPS65983B which is NRND.

Brian already responded for the USB hub devices, but just going to add information for the PD controller devices in addition.

Asaf Pipman said:

1. I'm concerned with what I think is a simultaneous dual role my tablet would to occupy in the USB scheme I had specified above. I think the tablet will take the host role on the client-module to tablet connection while simultaneously taking the role of client on the external PC to tablet connection. Is this something a DRD port is able to do?

I'm not sure if I understand this correctly, but you are expecting an external table to be able to simultaneously take the role of client and host? From the perspective of the PD controller, we can only advertise the port as a single Data and single Power role at one time. i.e. Data is either UFP(device) or DFP(host) and Power is either source or sink. You can have any combination of the source and sink roles, but the port will only ever advertise as one of the two roles. DRD means the port can support both UFP and DFP, but at separate times. It does not mean that there is a third Data role that allows the port to act as both UFP and DFP at the same time.

Asaf Pipman said:

Another possibility is since both the external PC port and the tablet port are DRD, they could negotiate the tablet as host and the PC as client, I assume. Can this last point be held while the external PC is acting as a power source and the tablet as a power sink?

As mentioned above, the power and data roles can be combined. Per the USB-C PD spec, a port can only enter in two combinations (Power Source and DFP or Power Sink and UFP), but immediately after individual data and/or power role swaps can be negotiated to get the desired port roles. Simultaneous Data roles are still not possible from the PD negotiation perspective.

Asaf Pipman said:

Does this negotiation require any intervention on my part or is this automatic?

There is some level of configuration where you can choose supported and preferred power and data roles when you generate the required FW image using the APP Customization GUI tool. This will configure the PD controller to support specific roles and can have the PD controller attempt to put the port into preferred roles.

If you need more control than that, you may need intervention through I2C.

Thanks and Regards,

Chris