so im in the process of trying to make my first PCB with USB 2.0 on it.
Right now im trying to work out what the trace width and clerance for the diffrential pair should be to get the correct impedance.
According to this: http://www.usb.org/developers/docs/hs_usb_pdg_r1_0.pdf
they normally use 7.5 mil(0.19mm) traces with 7.5mil clerance on a 63 mil board (1.6mm)
That should give the traces around 90 Ohms diffrential impedance acording to the PDF, but when i try to input it to my impedance calculator (Saturn PCB toolkit V7.03) it gives me: almost 160Ohm - and even if use 53mil "Conductor height" or anything i cannot get the 90 Ohm diffrential impendace - What are im doing wrong here?
Best regards Martin