Try this

http://indy2.automata.com/tools/imped/imped-ems.unsafe.html

Jeff Cole
Battelle PNNL
Scientific Engineering Associate
(509) 375 - 2758 PH
(509) 372 - 4725 Fax
[log in to unmask]

        -----Original Message-----
        From:   Daniel A. Doherty [SMTP:[log in to unmask]]
        Sent:   Thursday, February 18, 1999 11:27 AM
        To:     [log in to unmask]
        Subject:        [DC] Embedded Microstrip

        Does anyone happen to know the CORRECT formula for the capacitance of an
        embedded micstrip?  The one contained in -D-317A pg. 23 cannot be right
        as the natural log of a negative number is not defined...

        317A states:  C=(1/(H+t))*ln(1-(.6987*(E+1.41)/sqrtE))


        Daniel A. Doherty
        North Coast Design
        6341 Applewood Ln.
        Williamsburg, MI 49690-9725
        V 616.267.9717
        F 616.267.9718

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