TPS25741: USB Type-C power management controller for USB Accessory Box product

Hello Shlomi,

I have a few questions about your design before I can give you a final recommendation.
1. Is 5V the only voltage you are wanting to use for your design?
2. Are you going to be handling data or any alternate modes with this design?
3. Is your product the accessory box in the word document you sent?
4. What does HMD stand for and what is it?

Hi Adam,

 

Please find below the answers to your questions:

 

1. Is 5V the only voltage you are wanting to use for your design?

               (Shlomi) The board will need also a 3.3V for its internal circuit.

2. Are you going to be handling data or any alternate modes with this design?

               (Shlomi) The data interface between the HMD and the USB Accessory Box is USB 2, Full and/or High speed (Type-C connector will be used). No alternate modes will be used.

3. Is your product the accessory box in the word document you sent?

               (Shlomi) Yes, I will design the USB Accessory Box.

4. What does HMD stand for and what is it?

               (Shlomi) HMD stands for Head Mounted Display. This is a product which mostly used for virtual reality as the computing and display device for the user. I using an Off-the-Shelf product with USB Type-C receptacle which will be connected to my Accessory Box via a cable and Type-C plug.

 

Thanks,

Shlomi

 

Hi Adam,

I changed the system configuration and I would like to ask again for components recommendations to implement in my design

The system contains 3 USB products:

1. HMD (Head Mounted Display) - Off the Shelf product which has a USB Dual Role Port.

2. Accessory Box - Design by my, has an internal USB device functioning as Upstream Facing Port. I assume that a USB Hub component/function will be required for this product.

3. Maintenance PC - Off the Shelf product which has an internal USB device functioning as Downstream Facing Port.

 

The product will have two modes of operation:

1.      Standard Mode –

·       During standard operation, the HMD will function as USB host and our product will receive it's 5V supply from the USB VBUS of the HMD, data interface is Full/High Speed USB 2.0.

System diagram for Standard Mode attached.

 

2.      Maintenance/Charging Mode –

·       In this mode a PC will be connected to the Accessory Box as USB host (DFP), the PC will provide VBUS and communicate with the HMD and USB Device as Full/High Speed USB 2

System diagram for Maintenance/Charging Mode attached.

Thanks,

Shlomi

 

Standard & Maintenance Charing Mode.docx

Hello Shlomi,

1. Just to clarify on what you are stating, you are wanting your system to both sink power from the HMD as well as source power to the HMD? For terminology, this is called a Dual Role Port (DRP).
2. Will all three of the USB products be acting as a DRP?
3. Will all three of these ports be a Type C port?

Adam,

See my answers:

1. Just to clarify on what you are stating, you are wanting your system to both sink power from the HMD as well as source power to the HMD? For terminology, this is called a Dual Role Port (DRP).

During Standard Mode the HMD will source power to the Accessory Box and during Maintenance/Charging Mode the HMD will sink power from the Charger/PC via the Accessory Box. DRP was the exact terminology I used in my description and in the drawings.

2. Will all three of the USB products be acting as a DRP?

        No. Just the HMD is a DRP device. The PC is only DFP and the internal USB device in the Accessory Box is only UFP.

3. Will all three of these ports be a Type C port?

There are only 2 Type C ports, 1 for the PC/Charger connection and 1 for the HMD connection. The USB device inside the Accessory Box is connected internally without connector. Please look again in the drawings for better understanding the configuration.

I think the Accessory Box should have internally an internal USB2 Hub functionality with USB switches for the HMD dual functionality.

Thanks,

Shlomi

Hello Shlomi,

I did not realize that the device will be acting as a DRP. In that case, you will need to use a TPS6598x PD controller as those are the only parts that offer DRP capabilities. I would recommend using the TPS65986

For the internal UFP device you will need to use the TPS65986 as well as we do not have Type-C controllers that act solely as a UFP device.