HD3SS3212-Q1：use HD3SS3212-Q1 and TUSB321RWBR but no Superspeed

Hi,

Part of the issue is the routing of the SSTX and SSRX is not correct as shown below.

The ID pin and VCONN_FAULT also need to be pulled up to 3.3V through 200k resistor if not being used.

For this design, you can also refer to this design, https://www.ti.com/lit/ug/sllu241a/sllu241a.pdf.

Thanks

David

Hi, David. Thank you for your reply.

I don't understand where is error in SSTX and SSRX, besides T/RX's positive and negative reversed in C port.

I designed it with reference from two circuit in their datasheet.

Can you speak more clearly?

Thanks a lot.

peichun

Peichun

The output and input is defined by the USB connector. In the case below, SSTX is defined as an output while SSRX is defined as an input.

In your design, let's say the data comes into RX1 or RX2 (1), connected to HD3SS3212 B1 or C1 (2), and goes out to HD3SS3212 A1 (3). In this case, you would then to connect to SSTX of the USB Type-A receptacle. Right now, you connected to SSRX of the USB-A receptacle which is an input (4).

Thanks

David

So, USB Type-A's T/RX need to exchange ?

As shown below :

Thanks a lot.
peichun.

Peichun

This is correct, and you can use this design as a reference, https://www.ti.com/lit/ug/sllu241a/sllu241a.pdf.

Thanks

David

Hi,Daivd.

I follow do it, but it's still show highspeed. Is there anything else I ignore?

Thanks a lot.

peichun.

Peichun

Can you please replace the capacitors on TX1 and TX2 with 0-ohm resistors?

Can you also probe CC1, CC2, and SEL pin when Type-C cable is inserted in normal or flip orientation?

Thanks

David

David

I replace the capacitors on TX1 and TX2 with 0-ohm resistors.

Then, I measure the CC1, CC2, and SEL's voltage. The result is as follows.

Picture 1 : SEL=L, CH1=CC1, CH2=CC2

Picture 2: SEL=H(3V), CH1=CC1, CH2=CC2

Thanks a lot

peichun

Peichun

Here is the HD3SS3212 selection table,

When SEL = L, A0 connected to B0, which is CC1, you need to connect to TX1/RX1. 

When SEL = H, A0 connected to C0, which is CC2, you need to connect to TX2/RX2. 

Right now, in your design, you have them connected backward.

Thanks

David

I know I accidentally reversed channel A and channel B.

But does it matter?

Doesn't this only affect normal and reverse insertion in Type c?

Thanks a lot

peichun

Peichun

Yes, it does. For Type-C normal orientation, SuperSpeed data will be communicated across TX1/RX1. For flip orientation, SuperSpeed data will be communicated across TX2/RX2. Right now, the data is not being communicated across the right SuperSpeed data lanes.

Thanks

David

Ok, thank you so much, David.

I appreciate it !

peichun