Re: [SI-LIST] : Inductance vs. frequency

rbmccammon@mmm.com
Fri, 24 Apr 1998 13:29:20 -0500

I don't know chips and fine lines, but I would guess that at 10MHz+ yo=
u
would be in the LC regime rather than in the RC regime.

Thank you for your response. My guess is that if we measure R at DC, th=
en
the whole RC delay can be off 10X at 10MHz, or even more at 100MHz. Whi=
ch I
haven't seen on chips.
May be someone in this group can comment on it for us.

/frank
frank@chip-chip.com
-----Original Message-----
From: rbmccammon@mmm.com <rbmccammon@mmm.com>
To: Chip Chip <chip@chip-chip.com>; si-list@silab.eng.sun.com
<si-list@silab.eng.sun.com>
Date: Friday, April 24, 1998 10:08 AM
Subject: Re: [SI-LIST] : Inductance vs. frequency

>I can't give you an absolute answer, but it looks constant from 0 to 1=
0KHz
>and rises approximately as the square root of frequency from 100KHz to=

>10MHz.
>That's about what I would expect from skin effect.
>
>
>
>
>
>Hi, interesting data.
>
>One quesiton, the resistance goes up 10X from DC to 10MHz, isn't that =
too
>high ?
>
>/frank
>-----Original Message-----
>From: rbmccammon@mmm.com <rbmccammon@mmm.com>
>To: si-list(a)silab.eng.sun.com <si-list@silab.Eng.Sun.COM>
>Date: Thursday, April 23, 1998 10:25 AM
>Subject: RE: [SI-LIST] : Inductance vs. frequency
>
>
>I have some inductance data on 22 gauge high capacity twisted pair
>telephone
>cable.
>parameters are Hz, ohm/mile, mH/mile, umho/mile, uF/mile
>
> f R L G C
> 0 166.8 .802 --- .0825
> 1K 166.9 .798 1.2 .0820
>10K 168.6 .792 30.2 .0817
>100K 209 .773 603 .0810
> 1M 545 .654 8900 .0808
>10M 1725 .593 78400 .0808
>
>The inductance in this data is at least qualitatively
>similar to your data.
>
>I believe this data was determined by measuring characteristic
>impedence, propagation attenuation, and propagation velocity
>and then calculating R,L,G,C to match the data.
>
>
>
=