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USB superspeed peripherals

OfOr_1738446
Level 3
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Level 3

Hello,

I'm designing a new board with Fx3 and USB type C connector.

I saw that in-order to use the flip-ability of the type C I need to use a mux for the SS lines.

Can I just connect the SS_RX1_N and SS_RX2_N (and all the other SS) together and connect it to the Fx3?

Plus, I saw that I can connect my SS_TX_P net to the SS_TX_N pin and vise-versa (also SS_RX_P and SS_RX_N). Is it correct?

Thanks,

Ofer.

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1 Solution
RajathB_01
Moderator
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Moderator

Hi Ofer,

Flip need not be handled on TX/Rx if you are designing a device with Type-C plug. The host end will implement flip if it has Type-C. You can route just one lane of SS from the connector to the FX3 PHY and leave the other lane on the connector open (NC).

TX_P and TX_N will not get flipped when using single lane and SS PHY is designed to internally handle differential pair flips.

If you are designing for receptacle, please use a Superspeed Mux. Shorting TX1 pair with TX2 pair, or RX1 pair with RX2 pair is not recommended at SS bitrates.

For more details refer to the KBA pointed out by Muthu.

Regards,

Rajath

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3 Replies
MuthuM_11
Employee
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OfOr_1738446
Level 3
25 replies posted 10 replies posted 10 questions asked
Level 3

Hi Muthu,

Thanks for you like, it is very helpful.

What about the flip of the TX_P and TX_N lines?

All the best,

Ofer.

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RajathB_01
Moderator
Moderator 250 replies posted 100 replies posted 50 replies posted
Moderator

Hi Ofer,

Flip need not be handled on TX/Rx if you are designing a device with Type-C plug. The host end will implement flip if it has Type-C. You can route just one lane of SS from the connector to the FX3 PHY and leave the other lane on the connector open (NC).

TX_P and TX_N will not get flipped when using single lane and SS PHY is designed to internally handle differential pair flips.

If you are designing for receptacle, please use a Superspeed Mux. Shorting TX1 pair with TX2 pair, or RX1 pair with RX2 pair is not recommended at SS bitrates.

For more details refer to the KBA pointed out by Muthu.

Regards,

Rajath

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