Re: Line Parameters of Twisted Cables ?

Weston Beal (beal@galois.eng.hou.compaq.com)
Wed, 9 Apr 97 12:03 CDT

Bardo,

In the book _Microwave_Engineering_ by David Pozar, he gives the
formula for RLGC of two round conductors with a radius, 'a' with a
center to center distance, 'D' as:

L = (mu/pi)cosh^-1(D/2a)

C = (pi*eps')/(cosh^-1(D/2a)

R = Rs/pi*a

G = (pi*w*eps'')/cosh^-1(D/2a)

Rs is the resistivity
w is omega (frequency)
mu is permeability of free space * relative permeability
eps' is permittivity of free space * relative permittivity
eps'' is a factor in calculating the loss tangent

I hope this helps some.

Regards,

-- 
Weston Beal                Signal Integrity Engineer    
beal@twisto.compaq.com     beal@bangate.compaq.com
"A little bit of knowledge is a dangerous thing"

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Dear SI engineers,

anyone out there having data/formulas or a handy tool for the transmission line parameters (RLCG) and loss effects of twisted cables (over ground) ?

Thanks for any pointer,

Bardo Mueller ------------------------------------------------------------------- Dr. Bardo MUELLER Temic TELEFUNKEN microelectronic GmbH Bardo.Mueller@ulm.temic.de Design Center Integrated Circuits Tel. +49 (0)731 505 1212 Wilhelm-Runge-Str. 11 Fax +49 (0)731 505 1314 D-89081 ULM Germany