[SI-LIST] Re: PCIe failure due to too fast of an edge?

  • From: Neo <neoflash2008@xxxxxxxxx>
  • To: si-list@xxxxxxxxxxxxx, Tom Zych <Tom_Zych@xxxxxxxxxxxxxxxxxxx>
  • Date: Mon, 22 Dec 2008 17:35:59 -0800 (PST)

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
  

Other related posts: