[SI-LIST] Re: single RLC parameters at a certain frequency

  • From: steve weir <weirsi@xxxxxxxxxx>
  • To: xuzhengrong <Zhengrong.Xu@xxxxxxxxxx>
  • Date: Mon, 19 May 2008 21:01:55 -0700

Xuzhengrong, you can understand this by looking at a network of multiple
unique RLGCs. When trying to represent the network with a simpler single
RLGC the values for the most accurate fit depends on what the frequency
band is.

Steve.
xuzhengrong wrote:
> Hi,
> To simplify the model, we often extract single RLGC parameters from the
> s-parameter model at a certain frequency.
> I wonder what on earth the meaning of the single frequency parameters is.
> First, if the parameters only represent the magnitude and phase of the
> S-parameter model at the frequency point, it may have different combinations
> of RLGC to reach the same goal, what's the method or principle?
> Second, if the parameters are meaningful at a certain frequency, why can
> single RLGC parameters often be used to estimate characteristic of package
> model such as IBIS?  
>
> In my opinion, for example, the single RLGC model should be the first-order
> approximation to the real model for transmission line, as Eric's book
> 'Signal Integrity: Simplified' said.
> It is equivalent to the real model within low frequency range and we can use
> it if the signal frequency component is within the range.
> However, if the RLGC model extracted at a certain frequency is only
> meaningful for the extracting frequency, it isn't the first-order
> approximation for the transmission line.
> So we can't use it as the first-order approximation and estimate its low
> frequency characteristic. 
>
>
> Appreciate any idea and discussion for the problem.
>
> Best Regards,
> Zhengrong 
>
> ------------------------------------------------------------------
> 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 technical documents are available at:
>                 http://www.si-list.net
>
> 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
>   
>
>
>   


-- 
Steve Weir
Teraspeed Consulting Group LLC 
121 North River Drive 
Narragansett, RI 02882 

California office
(866) 675-4630 Business
(707) 780-1951 Fax

Main office
(401) 284-1827 Business 
(401) 284-1840 Fax 

Oregon office
(503) 430-1065 Business
(503) 430-1285 Fax

http://www.teraspeed.com
This e-mail contains proprietary and confidential intellectual property of 
Teraspeed Consulting Group LLC
------------------------------------------------------------------------------------------------------
Teraspeed(R) is the registered service mark of Teraspeed Consulting Group LLC

------------------------------------------------------------------
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 technical documents are available at:
                http://www.si-list.net

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
  

Other related posts: