*From*: <Alex_Messan@xxxxxxxx>*To*: <si-list@xxxxxxxxxxxxx>*Date*: Thu, 31 Aug 2006 00:16:13 -0500

Kranthi, What is important in the equations is to realize that they are worst case scenarios (minimal margin). In common clock environment, an early clock edge reduces setup margin while a late clock edge reduces hold margin. Regards, Alex -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of kranthi Sent: Wednesday, August 30, 2006 11:50 PM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Timing equations - help Hi, I have a doubt in timing equations for calculating the setup and hold margins.i referred few documents but, were very confusing and so I did not have another option other than posting it on this group. The cause of confusion is the clock skew parameter.some documents subtract it for calculating the set up margin and add it for calculating the hold margin while others do the opposite way.One point to be noted is that the skew can be positive or negative.So, what is the exact way in which the skew should be accounted.i have a general conception that, If the clock skew is positive then Tclk_skew should be added in setup_margin equation and subtracted in hold_margin equation, and when the clock skew is negative it should be taken the opposite way.Is this conception correct? Please help me on the exact way of considering this parameter(clock skew) in estimating the setup and hold margins. Best regards, Kranthi ------------------------------------------------------------------ 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

**References**:**[SI-LIST] Timing equations - help***From:*kranthi

- » [SI-LIST] Timing equations - help
- » [SI-LIST] Re: Timing equations - help
- » [SI-LIST] Re: Timing equations - help
- » [SI-LIST] Re: Timing equations - help
- » [SI-LIST] Re: Timing equations - help