HI Ma, Infineon had a JEDEC showing regarding a 4 slot DDR2 system and ODT configuration. Do you have access to JEDEC documents ? You might search for DDR2 4 slot documents. If you can find nothing I can provide more details. Regards hermann =20 -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of Zhuofan Ma Sent: Saturday, August 13, 2005 8:27 PM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] DDR2 ODT configuration Hi all, =20 Recently,I was doing a SI simulation on 400MTS DDR2 signals,with 4 DIMM slots. I notice that memory chip vendors introduce one and two DDR2 module ODT configuration scheme. When two module populated, the ODT will be turned off at active module and turned on at standby module. But if the active module is at far side to the memory controller, should the ODT at close standby module also be turned on? As to 4 DIMM slots, if one module at different position is activated, how should other three modules ODT be configured? In my opinion, only the farthest module ODT should be turned on. Is that correct? Could anyone give me some recommendation for how memory controller configure the standby modules ODT? Btw, I've tried some different ODT schemes, but I wonder why the simulation results are pretty similar? Thanks in advance for any advice or help. =20 Sincerely, Ma ------------------------------------------------------------------ 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: =20 //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: //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