multilayer PCB and impedance matching

[Thiago]

I need to design a PCB for USB 2.0 applications but I have no experience on
impedance matching and multilayer PCB. It is recommended for USB 2.0 to use
4-layers. Does Eagle have any tools to automatically calculate the trace
impedance? Any tutorial about 4-layers PCB would help too.

Thanks

Thiago

[TP Electronics]

nei Eagle do not automatic but you can fin the rulles on web about the size
of track / laminat spesification.
But it is a ulp to show the length of a signal (length.ulp):
Done a 6 layer with USB 2.0 & PCI express +++ work perfect but take some
time when you must adjust le length.
See Help of lengh.ulp you can for command line :" run lengh d+ D-" and
retour the length and difference.
Thierry

Post by Thiago
I need to design a PCB for USB 2.0 applications but I have no experience on
impedance matching and multilayer PCB. It is recommended for USB 2.0 to use
4-layers. Does Eagle have any tools to automatically calculate the trace
impedance? Any tutorial about 4-layers PCB would help too.
Thanks
Thiago

[John Miles]

Post by Thiago
I need to design a PCB for USB 2.0 applications but I have no experience on
impedance matching and multilayer PCB. It is recommended for USB 2.0 to use
4-layers. Does Eagle have any tools to automatically calculate the trace
impedance? Any tutorial about 4-layers PCB would help too.

Cypress has an app note with USB PCB layout recommendations:
http://www.cypress.com/design/AN1168

Also see:
http://classes.engr.oregonstate.edu/eecs/fall2004/ece441/groups/g26/whitepapers/White%20Paper.doc
(Word 6.0 document)

-- john, KE5FX