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Can the positive and negative line of USB3 SS connections be swapped?

I ask this, as I have seen that it was done in the schematic of the Cypress FX3. Or is this an error in the schematic representation?

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JRE
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Botnic
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1 Answers1

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According to AN70707 Page 16:

The polarity can be swapped on the USB 3.0 differential pairs. Polarity detection is done automatically by the USB 3.0 PHY during link training, as define in the USB3.0 specification section 6.4.2, and does not require any additional changes to device Firmware. Given the different USB connectors pin-out, the polarity inversion mechanism can be utilized to ensure that USB traces do not cross each other.

Botnic
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  • What does "the polarity inversion mechanism can be utilized to ensure that USB traces do not cross each other" mean? – Navin Mar 03 '17 at 07:44
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    USB 3.0 standard does have the "polarity inversion mechanism" implemented in hardware. "Can be utilized" means that you better route the trace pair in best way to keep signal integrity rather than twisting them to meet + and - polarity. – Ale..chenski Mar 03 '17 at 18:50