FreeLists / si-list / [SI-LIST] Re: what is the conductivity of a dielectric?

[Greg Beck <gbeck@xxxxxxxxxxxxxxxxx>]

I would contact some of the big laminate makers:

http://www.isolalaminatesystems.com [1]
http://www.parknelco.com/parknelco/ product.htm[2]
http://www.rogers-corp.com
http://www.ge.com/electromaterials[4]
http://www.taconic-add.com/
Greg Beck
VP Sales &Marketing
Optimum Design Associates-PCB Layout &Engineering
p 925.551.4155 x109
c 408.515.1070
www.optimumdesign.com[6]


>Transmission line gurus and people who love dielectrics--

>I am trying to figure out the conductivity of a dielectric.
>I have an equation that gives me:
>tanD = 1/(2*pi*Freq*Er*rd) where rd is the resistivity of the dielectric
>I assume that 1/rd is the conductivity of the dielectric. Is that an
>erroneous assumption?
>That gives me the equation:
>conductivity of dielectric = 2*pi*Freq*Er*tanD

>This second equation makes sense to me in that increasing your frequency
>increases the dielectric conductivity, causing more "leakage" of your
>transmitted energy. However, using this equation, that would indicate that
>the conductivity of a dielectric with Er=4 and tanD=0.02 would have a
>conductivity approaching that of copper at 100MHz. Now that does not make
>sense.

>Is there a such thing as non-frequency-dependent conductivity of a
>dielectric? How would I obtain such a number?
>Is there something else I am missing?

>Any guidance would be greatly appreciated. Thanks.
>--Pat




>------------------------------------------------------------------
>To unsubscribe from si-list:
>si-list-request@xxxxxxxxxxxxx[7] with 'unsubscribe' in the Subject field

>or to administer your membership from a web page, go to:
>http://www.freelists.org/webpag e/si-list[8]

>For help:
>si-list-request@xxxxxxxxxxxxx[9] with 'help' in the Subject field

>List archives are viewable at: 
>http://www.freelists.org/archives/s i-list[10]
>or at our remote archives:
>http://groups.yahoo.com/group/si-li st/messages[11] 
>Old (prior to June 6, 2001) list archives are viewable at:
>http://www.qsl.net/wb6tpu[12]
>







--- Links ---
   1 http://www.isolalaminatesystems.com
   2 http://www.parknelco.com/parknelco/product.htm
   3 http://www.rogers-corp.com
   4 http://www.ge.com/electromaterials
   5 http://www.taconic-add.com/
   6 http://www.optimumdesign.com
   7 mailto:si-list-request@xxxxxxxxxxxxx
   8 http://www.freelists.org/webpage/si-list
   9 mailto:si-list-request@xxxxxxxxxxxxx
  10 http://www.freelists.org/archives/si-list
  11 http://groups.yahoo.com/group/si-list/messages
  12 http://www.qsl.net/wb6tpu
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field

or to administer your membership from a web page, go to:
http://www.freelists.org/webpage/si-list

For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field

List archives are viewable at:     
                http://www.freelists.org/archives/si-list
or at our remote archives:
                http://groups.yahoo.com/group/si-list/messages 
Old (prior to June 6, 2001) list archives are viewable at:
                http://www.qsl.net/wb6tpu