Can USB2.0 pair (D+, D-) of CYUSB3014 swappable?

[Anonymous]

 When we layout the PCB of our first USB3.0 product, we found that the D+ (A9) and D- (A10) have to be crossed each other when rounting to the type B USB receptable connector (Pin3 is D+, Pin2 is D-), we're using Type-B through hole receptable and USB3.0 chip (3014) on the same side, In Appilcation Notes 70707, there's part of the pcb layout which doesn't show such cross...we're wondering if we made mistakes on the pin layout of the USB chip or the USB connector...but we checked several times....AN70707 mentioned the USB3.0 pairs can be swapped ...but not mention the USB2.0 pair ...any clue? Thanks!

[Anonymous]

The short answer is No.

   

Swapping of the USB3.0 lines is defined by USB protocol itself to make routing of these very high frequency lines easier. This is checked by host PHY when the device is plugged in and the host accordingly changes the signaling being driven. 

   

This is not the case for USB2.0.

   

Regards,

   

Anand

[Anonymous]

Anand,

   

  Thanks, i guess the "crossing" route is done near the end of chip (pin A9 and pin A10), thus we saw a "length compensation" on the USB connector side (on AN70707).

   

JT