At 03:07 PM 6/5/00 +0100, you wrote:
>Hi there, methinks me & others have been asking the same thing.
>Could not find any web addresses, but here the text of the only reply
>follows.
>Please keep us informed if you manage to find anything on the subject.
>Many thanks - Matt
><SNIP>
>1) a circular inductor with an outer diameter of D and an inner diameter
>of d will have an inductance of approximately :
>0.492 L [nH] = ----------------- (D[mm]+d[mm])^2 n^2 2.25D[mm]-0.25d[mm]
>if you use a central via then d becomes 0.
>Elektronische Bauelemente, Michael Reisch, Springer-Verlag Berlin
>Heidelberg 1998, p. 135
>2.) a circular inductor with an outer diameter of E[cm] and a radius of
>r[cm] will have an inductance of approximately;
>21.5 n^2 (E-r) L[nH] = ----------- r 1+2.72 ----- (E-r)
>Das grosse Werkbuch Elektronik Bd2, Dieter Nuehrmann, Franzis' Verlag
>1998, p.1153
><SNIP>
>
>>-----Original Message-----
>>From:  McGlaughlin, Jeffrey A [SMTP:[log in to unmask]]
>>Sent:  Monday, June 05, 2000 2:09 PM
>>To:    [log in to unmask]
>>Subject:       [DC] Planer Inductors
>>
>>Does anyone know of a good set of design guides and equations for designing
>>a planer inductor?
>>The specifications I have are 22 uH (microHenry) with  4 ohm resistance
>>maximum O.D. of 2mm on FR-4.
>>I don't think this is possible but would like the math to prove it.
>>
>>TIA,
>>Jeffrey A. McGlaughlin, C.I.D.
>>Sr. PCB Designer
>>Battelle Memorial Institute
>>Columbus Ohio
>>[log in to unmask]
>

Greetings,

I will be away from my e-mail for a few days.
please contact:
[log in to unmask] for any pcb design issues
[log in to unmask] for any other issues

Thanks,



Leonard Toohey
CAD Applications Engineer
Cisco Systems, Inc.
12515 Reasearch Blvd.
Building 4
Austin, Texas 78759-2220
512 378-1227 (direct)
512-378-1251 (fax)
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