[SI-LIST] Re: Impedance confusion

Study Yuriy's comments carefully. 

Steve.
Lakshmi N. Sundararajan - PTU wrote:
> Actually my confusion arose from using Polar for impedance calculation
> for edge coupled offset stripline.
> There is an input H1, which is the height of the trace from the plane,
> now this can be either 5 mils or 22 mils depending...
> The impedance varies based on which value I choose?!
>
> Is there a rule to pick only one of these two?
>
> Thanks,
> -LN
>  
>
>   
>> -----Original Message-----
>> From: Doug Brooks [mailto:dbrooks7@xxxxxxxxxx] 
>> Sent: Friday, November 21, 2008 1:18 PM
>> To: Lakshmi N. Sundararajan - PTU; si-list@xxxxxxxxxxxxx
>> Subject: Re: [SI-LIST] Impedance confusion
>>
>> Your confusion may be because:
>> Offset stripline implies a single-ended impedance, while 
>> edge-coupled offset stripline implies a differential impedance.
>> If the stackup is
>> sig --- plane --- sig --- sig --- plane --- sig The inner 
>> layers are asymetric stripline from a single-ended 
>> standpoint, and if there is parallel coupling between the two 
>> inner signal layers that coupling is broadside differential 
>> coupling (unless, of course, it is simple crosstalk 
>> coupling.) Hope that helps.
>>
>>
>>
>>
>>
>>
>> At 12:18 PM 11/21/2008, you wrote:
>>     
>>> Hi Team,
>>>
>>> Between these two stackup,
>>> a) SIGTOP-PP(5 mils)-SIGINNER1-PP(22 mils)-SIGBOT
>>> b) SIGTOP-PP(22 mils)-SIGINNER2-PP(5 mils)-SIGBOT
>>>
>>> While computing the impedance of the SIGINNER* layer, it is offset 
>>> stripline or edge coupled offset stripline.
>>>
>>> Would the impedance be different between these two cases?
>>> I ask this because, when board (a) is rotated it becomes 
>>>       
>> board (b) and 
>>     
>>> hence I do not expect impedance to vary between these two stackups.
>>>
>>> Can anyone please confirm/clarify on this.
>>>
>>> Thanks,
>>> -LN
>>> ------------------------------------------------------------------
>>> 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
>>>
>>>       
>>
>>
>>     
> ------------------------------------------------------------------
> 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: