Try this book:

"Transmission Line design Handbook"
by Brian C Wadell
Artech House

At 17:19 11/11/97 -0500, you wrote:
>Does anyone know the formula(s) for calculating the impedance of
>differential pairs when the lines are on adjacent layers to one another
>and NOT side by side on the same layer, or perhaps software that handles
>this type of configuration? This does not appear to be covered in
>IPC-D-275.
>
>Thanks in advance for any enlightenment.
>
>        Brock
>
>+-----------------------------------+
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Gwen Merchant - Marketing Support
Polar Instruments Ltd.
Tel: +44 1481 53081
Fax: +44 1481 52476
http://www.polar.co.uk
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