When you say "there is no effect on SI quality and timing" do you mean "as predicted by my SI tools" or "based on real-world measurements"? Todd. Todd Westerhoff SI Engineer - Hammerhead Networks 5 Federal Street - Billerica, MA - 01821 email:twester@xxxxxxxxxxx - ph: 978-671-5084 ============================================ "Oh, but ain't that America, for you and me Ain't that America, we're something to see Ain't that America, Home of the Free Little pink houses, for you and me" - John Mellencamp -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx]On Behalf Of Goutham.S@xxxxxxxxxx Sent: Monday, October 29, 2001 4:28 AM To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] SPLIT PLANE GAP Hi AGTLP signals are passing over a split plane (3.3v plane Vtt plane). Frequency of these signals is 133MHz. Rise time & Fall times are 0.75ns, 0.9ns respectively. These signals are routed on BOTTOM layer (Micro strip). 3.3 v plane and Vtt plane split gap is 100mil maximum. ----------------Top layer ----------------Gnd ----------------Signal ----------------Signal ----------------3.3v & VTT (split) ----------------Bottom layer I have found there is no effect of split gap (25mil to 100mil) on signal quality and timing. We can calculate wavelength from Tr & Tf values, but what is the maximum split gap can be allowed for such a design? I don't know how much it will affect EMI, can any one suggest? regards Goutham Sabavat ------------------------------------------------------------------ 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 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 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