Can I reversely route the data polarity to USB common mode filter below? Namely, connect USB trace D+ to the filter pin D- to simplify layout.
http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00039389.pdf
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6\$\begingroup\$ There does not seem to be anything in the datasheet which would indicate this is a problem. The internal schematic looks symmetrical. However there is nothing saying it's fine either, so test it and see. \$\endgroup\$– DavidCommented Nov 17, 2015 at 23:37
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4\$\begingroup\$ I also think it's fine. You could also ask on the ST forum, just in case... \$\endgroup\$– got trolled too much this weekCommented Nov 18, 2015 at 2:17
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1\$\begingroup\$ I am squeamish about a polarity reversal. \$\endgroup\$– AutisticCommented Nov 18, 2015 at 9:46
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1\$\begingroup\$ The AC USB signal is differentially bipolar and the DC pullup can be on either side depending on device speed, so it's hard to see how the filter could care. \$\endgroup\$– Chris StrattonCommented Nov 20, 2015 at 20:10
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1\$\begingroup\$ @ChrisStratton I tend to agree with you, but the nature of a coupled inductor, which is what the datasheet pictures and descriptions suggest is inside the IC, would lead me to believe it may not behave symmetrically if the data lines are swapped. As an aside, I don't see how swapping the data lines helps routing in anything other than the most trivial sense, but I digress. \$\endgroup\$– AnthonyCommented Nov 24, 2015 at 19:23
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I think you can do it because, like the commenters have pointed out, the common mode circuit is symmetrical. But why wouldn't you just to go for sure turn the component by 180°?
