I probably should clear something up on our excel spreadsheet approach : the pcb trace delays in our excel spreadsheet are quantified by ICX, so this approach stands up to a lot high speed issues (xtalk, settling time, etc.). The only thing the excel spreadsheet is doing is keeping track of everything (it budgets trace delays before pcb design, and it tallies the real delay (via ICX) after pcb design). Also, keep in mind we're talking board level timing (original question), so it includes trace delays, chip delays, clk skews, etc. for all interfaces. Using ICX (or a similar tool) just gives you one component - a very important component - but we still need everything else. Jp -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx]On Behalf Of Bill Wurst Sent: Friday, September 24, 2004 11:33 AM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: On a different note .... As clock rates increase and timing margins shrink, it seems to me that crosstalk induced timing modulation is becoming more of an issue, both on ASICs and PCBs. This and the complexity of todays designs will probably force us to move away from Excel spreadsheets which I, like many others, haveused for timing analysis. What I mean by crosstalk induced timing modulation is this: Envision a victim net with with one or more aggressors. At roughly this same time that the victim transitions, the aggressor(s) transition also. Depending on whether the aggressors move in the same or opposite directions, the timing on the victim will either be advanced or retarded. Admittedly, this variation is small (on the order of the transition time of the signals involved), but timing margins today are often of the same order or less. It would seem that tools like Mentor's ICX / Tau combination are ideally suited to analyze this situation on PCBs (IBM's static timing tool, Einstimer, has had this capability for a couple of years now for ASICs). Does anyone know if this capability exists in Mentor's tools yet (Mentor's salesmen told me this was coming a year ago) and if so, does it work? Does anyone have any experience with these tools to give some feedback. Another tool that was supposed to be enhanced for this capability is SiAuditor [1]from SiSoft[2]. Does anyone have any experience with this tool to report - good, bad, or otherwise? Thanks, -Bill ====================== Peterson, James F (FL51) wrote: yep - I agree with you in general, regarding home-grown tools. The excel approach to board level timing is simple and elegant - we dedicate a page to device timing, a page to trace timing, and then a page to each interface analyzed. We've found that it's easy to understand (you can past in timing diagrams, show the equations, and add notes to help understand each of the interfaces) and it's nice to have everything in one model. We've been using it for around 4 years now and there are so many positives that the EDA vendortool that wants to compete will have a tough sell. But that said, thereare some out there that have some potential - I believe Mentor's TAU is one of them. I mentioned there are some weaknesses to our approach. It's cumbersome for us to break down a bus to the individual signal level : when we give a min/max it's at the bus level. the challenge is, say on a hold timeissue, that the signal whose trace has the quickest settling time on the bus, doesn't have the quickest Tco(min) at the chip, so we're overly conservative. It's cumbersome for our approach to break this down, we can do it but it becomes complicated, and harder to understand and maintain. This iswhere the EDA tools that I've seen are more efficient. best regards, Jim -----Original Message----- From: steve weir [mailto:weirsp@xxxxxxxxxx[3]] Sent: Friday, September 24, 2004 7:51 AM To: james.f.peterson@xxxxxxxxxxxxx[4] Cc: si-list@xxxxxxxxxxxxx[5] Subject: Re: [SI-LIST] Re: On a different note .... Jim, one of the values that a vendor tool brings is that it doesn't loaddown the organization with the task of maintaining and training people oncustom in-house tools. In larger organizations, vendor tools even if priceymay pay back easily in terms of the scarce engineering resources that they save from non-core tasks. OTOH, some amount of in-house tools can provide an edge in cost or productivity, so mileage will definitely vary. Regards, Steve. At 04:23 AM 9/24/2004 -0700, Peterson, James F (FL51) wrote: Todd, without going into too much detail, an excel spreadsheet can be awesomefor developing (allocating and budgeting timing) and maintaining (back-annotating with actual timing) a board-level timing model (see my earlier reply in archives). there are some weaknesses in this approach that an EDA vendor can fix by creating/selling a custom tool, but I'm currently developing one for a board that has DDR SDRAM, QDR SRAM, and RapidIO with LVDS, SSTL and HSTL data rates at 250MHz, and it still works. best regards, Jim Peterson Honeywell -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx[6] [mailto:si-list-bounce@xxxxxxxxxxxxx[7]]On Behalf Of Todd Westerhoff (twesterh) Sent: Thursday, September 23, 2004 4:17 PM To: si-list@xxxxxxxxxxxxx[8] Subject: [SI-LIST] On a different note .... What techniques are people using to combine the results of static timing and signal integrity analysis for closing timing at the board/system level? This is a question I've asked a few times before, usually with mixed responses. Because the choices for board-level static timing tools are relatively few, I'm curious as to which tools are used productively, and how. Replies on and off the list are welcome. Thanks, Todd. Todd Westerhoff High Speed Design Specialist Cisco Systems 1414 Massachusetts Ave - Boxboro, MA - 01719 email:twesterh@xxxxxxxxx[9] ph: 978-936-2149 ============================================ "Always do right. This will gratify some people and astonish the rest." - Mark Twain ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx[10] with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list[11] For help: si-list-request@xxxxxxxxxxxxx[12] with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ[13] Listtechnical documents are available at: http://www.si-list.org[14] List archives are viewable at: //www.freelists.org/archives/si-list[15] or atour remote archives: http://groups.yahoo.com/group/si-list/messages[16] Old(prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu[17] ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx[18] with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list[19] For help: si-list-request@xxxxxxxxxxxxx[20] with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ[21] Listtechnical documents are available at: http://www.si-list.org[22] List archives are viewable at: //www.freelists.org/archives/si-list[23] or atour remote archives: http://groups.yahoo.com/group/si-list/messages[24] Old(prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu[25] ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx[26] with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list[27] For help: si-list-request@xxxxxxxxxxxxx[28] with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ[29] Listtechnical documents are available at: http://www.si-list.org[30] List archives are viewable at: //www.freelists.org/archives/si-list[31] or atour remote archives: http://groups.yahoo.com/group/si-list/messages[32] Old(prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu[33] -- -Bill William C. Wurst William C. Wurst 2 5 2004-09-03T11:07:00Z 2004-09-03T11:07:00Z 1 30 176 Advanced Electronic Concepts, LLC 1 1 205 11.6360 73 Clean Clean false false false Mi crosoftInternetExplorer4 /* StyleDefinitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} -Bill billw@xxxxxxxxxxx[34] Advanced Electronic Concepts, LLC www.aec-lab.com[35] Office: 603-672-4400 Cell: 603-305-3525 --- Links --- 1 http://www.sisoft.com/products.asp 2 http://www.sisoft.com/ 3 mailto:weirsp@xxxxxxxxxx 4 mailto:james.f.peterson@xxxxxxxxxxxxx 5 mailto:si-list@xxxxxxxxxxxxx 6 mailto:si-list-bounce@xxxxxxxxxxxxx 7 mailto:si-list-bounce@xxxxxxxxxxxxx 8 mailto:si-list@xxxxxxxxxxxxx 9 email:twesterh@xxxxxxxxx 10 mailto:si-list-request@xxxxxxxxxxxxx 11 //www.freelists.org/webpage/si-list 12 mailto:si-list-request@xxxxxxxxxxxxx 13 http://si-list.org/wiki/wiki.pl?Si-List_FAQ 14 http://www.si-list.org 15 //www.freelists.org/archives/si-list 16 http://groups.yahoo.com/group/si-list/messages 17 http://www.qsl.net/wb6tpu 18 mailto:si-list-request@xxxxxxxxxxxxx 19 //www.freelists.org/webpage/si-list 20 mailto:si-list-request@xxxxxxxxxxxxx 21 http://si-list.org/wiki/wiki.pl?Si-List_FAQ 22 http://www.si-list.org 23 //www.freelists.org/archives/si-list 24 http://groups.yahoo.com/group/si-list/messages 25 http://www.qsl.net/wb6tpu 26 mailto:si-list-request@xxxxxxxxxxxxx 27 //www.freelists.org/webpage/si-list 28 mailto:si-list-request@xxxxxxxxxxxxx 29 http://si-list.org/wiki/wiki.pl?Si-List_FAQ 30 http://www.si-list.org 31 //www.freelists.org/archives/si-list 32 http://groups.yahoo.com/group/si-list/messages 33 http://www.qsl.net/wb6tpu 34 mailto:billw@xxxxxxxxxxx 35 http://www.aec-lab.com/ ------------------------------------------------------------------ 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