[SI-LIST] Re: Slew Rate Calculation

you had to define your usage enviroment at first to see if you can
change termination.

If your board is embedded structure, you have chance to change the
termination R value. But if you use DIMM, the value of differential
termination R is already set. you can not vary it.

On 11/30/06, Tom Dagostino <tom@xxxxxxxxxxxxx> wrote:
> I can think of a few:
>
> Unmatched termination -> SI issues
> Stronger load -> lower voltage swing
> More current -> higher power dissipation
> More current -> more power supply noise
> Faster slew rate -> more radiation
> Faster slew rate -> more crosstalk
>
> Tom Dagostino
> Teraspeed(R) Labs
> 13610 SW Harness Lane
> Beaverton, OR 97008
> 503-430-1065
> tom@xxxxxxxxxxxxx=20
> www.teraspeed.com=20
>
> Teraspeed Consulting Group LLC
> 121 North River Drive
> Narragansett, RI 02882
> 401-284-1827
>
> -----Original Message-----
> From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] =
> On
> Behalf Of Bingipur, Arjun
> Sent: Thursday, November 30, 2006 12:35 AM
> To: si-list@xxxxxxxxxxxxx
> Cc: bennyzhi@xxxxxxxxx
> Subject: [SI-LIST] Re: Slew Rate Calculation
>
>
>
> Sorry, a typo. It is DDR2.
>
> Micron recommends a differential termination in the range of 100-120 =
> ohms
> between the clock pairs, which will yield a high slew rate. Probably =
> because
> of the small load. But, my optimal slew rate is achieved by tweaking the
> termination to around 33-35 ohms in the simulation. Does this in any way
> influence the performance?
>
> Regards,
> Arjun Bingipur
>
> -----Original Message-----
> From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx]
> On Behalf Of Benny Yan
> Sent: Monday, November 27, 2006 8:30 AM
> To: Bingipur, Arjun
> Cc: si-list@xxxxxxxxxxxxx
> Subject: [SI-LIST] Re: Slew Rate Calculation
>
> Should it be DDR2?
> It seems that the loading is too small, have you checked the model you =
> used?
> like package, C_comp...
>
> On 11/25/06, Bingipur, Arjun <arjun.bingipur@xxxxxxxxxx> wrote:
> >
> >
> > Hi,
> >
> > I'm doing a static timing analysis for determining the slew rate for
> the
> > differential clock signals of a DDR. When I do a slew rate derating=20
> > calculation on the eye diagram, I end up with values of around 6V/ns
> and
> > I 'm unable to consider this value to compare with the address/command =
>
> > derating values to arrive at the correct setup and hold time values in =
>
> > the data sheet.
> >
> > The topology is such that a controller is driving a single DDR with a=20
> > differential termination of 120 ohm connected close to the receiver
> IC.
> > Am I missing something here?
> >
> > Regards,
> > Arjun Bingipur
> >
> >
> >
> >
> ************************************************************************
> ***=3D3D
> > *************
> >
> > Note:  If the reader of this message is not the intended recipient, or
> an=3D3D
> > employee or agent responsible for delivering this message to the
> intended=3D3D
> > recipient, you are hereby notified that any dissemination,
> distribution
> > or=3D3D
> > copying of this communication is strictly prohibited. If you have=20
> > received=3D3D this communication in error, please notify us =
> immediately=20
> > by replying
> to=3D3D
> > the message and deleting it from your computer. Thank you.=3D3D0D
> >
> >
> >
> ************************************************************************
> ***=3D3D
> > *************
> > ------------------------------------------------------------------
> > 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:=20
> > http://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:
> >                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 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:    =3D0D
>                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
>  =3D0D
>
>
> *************************************************************************=
> **=3D
> *************
>
> Note:  If the reader of this message is not the intended recipient, or =
> an=3D
> employee or agent responsible for delivering this message to the =
> intended=3D
> recipient, you are hereby notified that any dissemination, distribution =
> or=3D
> copying of this communication is strictly prohibited. If you have =
> received=3D
> this communication in error, please notify us immediately by replying =
> to=3D
> the message and deleting it from your computer. Thank you.=3D0D
>
> *************************************************************************=
> **=3D
> *************
> ------------------------------------------------------------------
> 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 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:    =20
>                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
>  =20
>
>
> ------------------------------------------------------------------
> 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 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:
>                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 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:     
                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: