When we are designing the PCIe Gen2 Tx driver, the edge rate is very unlikely to be faster than 30ps due to the huge device/pad loading. This slow edge rate will be further slow down by bonding wire/bump and PCB trace. Furthermore, your scope will have difficulty to see <30ps edge rate if the scope bandwidth is lower than 8G. Regards, Neo --- On Tue, 8/19/08, Tom Zych <Tom_Zych@xxxxxxxxxxxxxxxxxxx> wrote: From: Tom Zych <Tom_Zych@xxxxxxxxxxxxxxxxxxx> Subject: [SI-LIST] PCIe failure due to too fast of an edge? To: si-list@xxxxxxxxxxxxx Date: Tuesday, August 19, 2008, 4:17 PM Hi all. I'm hoping someone can help me in gathering information for some research I'm doing. The PCIe Gen 2 spec includes a minimum risetime spec that, for 5 GT/s, works out to 30 ps. My question is, has anyone actually ever seen a device fail this spec? If you have, I'd be interested in knowing the characteristics of the measurement instrument (e.g. bandwidth, sample rate, etc.) as well as details of the conduction path (e.g. probe with X BW, SMA cable from a test fixture, connector torqueing, etc.) that you were using when you made the measurement. If you want to respond directly to me via email, I can ensure that your name/your company's name will not be released. Thanks, Tom ______________________________ Tom Zych Chief Engineer ASA Corp phone: +1-413-596-5354 FAX: +1-413-596-9686 ------------------------------------------------------------------ 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 technical documents are available at: http://www.si-list.net 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 technical documents are available at: http://www.si-list.net 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