[SI-LIST] Re: DRAM Address lines : Daisy Chain or "T"?
- From: steve weir <weirsp@xxxxxxxxxx>
- To: erwin-sp.seow@xxxxxx, "si-list" <si-list@xxxxxxxxxxxxx>
- Date: Mon, 26 Jul 2004 23:39:49 -0700
Erwin, if you make a T with significant stubs then you will need a driver
capable of driving one half the line impedance and separate damping
resistors for each of the two segments. If the segments are unequal
length, then you will also get some additional ringback.
If you drive a daisy chain, then if the nearest load will not settle until
2*Tflight_far - Tflight_near
Steve.
At 02:13 PM 7/27/2004 +0800, SEOW, ERWIN wrote:
>Hi SI gurus,
>
>I am presently routing a board using 2 DDR RAMS. I would like to know
>how do we route the common lines (Eg Address lines) ?
>
>Do we use Daisy Chain?
>
>Or a "T" where the driver is at the bottom and splits to each ot the
>DRAMS?
>
>Of the 2 methods, what are the pros and cons?
>
>Thanks in advance!
>
>Best regards
>
>Erwin Seow
>
>
>------------------------------------------------------------------
>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:
>//www.freelists.org/webpage/si-list
>
>For help:
>si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
>
>List FAQ wiki page is located at:
> http://si-list.org/wiki/wiki.pl?Si-List_FAQ
>
>List technical documents are available at:
> http://www.si-list.org
>
>List archives are viewable at:
> //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:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List FAQ wiki page is located at:
http://si-list.org/wiki/wiki.pl?Si-List_FAQ
List technical documents are available at:
http://www.si-list.org
List archives are viewable at:
//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:
