The statement is based on the idea that Vss stitching from bypass capacitor Vss vias and IC Vss vias is adequate. The idea concludes that explicit vias corresponding to signal or signal pair transitions are not necessary. Steve On 9/7/2014 2:46 AM, Leeyuyun wrote: > Stitching should be needed when gnd reference plane change > I do not know why you said do not need any stitching vias > I want to clarify my question as below > # means stitching vias, * means signal vias, + means positive signal, - means > negative signal > 1. Only on stitching vias > +++++++++++++++++*++++++++++ > # > --------------------------*---------------- > 2. At least two stitching vias > # > ++++++++++++++++*+++++++++++ > > ------------------------*------------------ > # > For each structure, what is theory behind? What is your recommendation for > stitching via structure in the 25Gbps structure? > >> "Lee " <leeritchey@xxxxxxxxxxxxx> 於 2014/9/7 上午3:17 寫道: >> >> No stitching vias are needed. Where did this idea get started? >> >> -----Original Message----- From: Leeyuyun >> Sent: Saturday, September 06, 2014 4:25 AM >> To: si-list@xxxxxxxxxxxxx >> Cc: lee.home.61@xxxxxxxxx >> Subject: [SI-LIST] One stitching via or more vias is better for 25Gbps >> application??? >> >> Hi, all >> I am doing 100Gbps (4x25Gps) product now >> How do we put stitching vias when high speed signal change the layer? >> This is a differential pair, which has P and N >> Someone told me that one stitching vias is better because P and N share the >> common return >> Someone told me that more stitching vias is better because loop inductance >> could be reduced more >> I am confused which one is better? >> Can anyone help me? >> Thanks, Lee------------------------------------------------------------------ >> 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 forum is accessible at: >> http://tech.groups.yahoo.com/group/si-list >> >> List archives are viewable at: >> //www.freelists.org/archives/si-list >> >> Old (prior to June 6, 2001) list archives are viewable at: >> http://www.qsl.net/wb6tpu >> >> >> >> >> ----- >> No virus found in this message. >> Checked by AVG - www.avg.com >> Version: 2014.0.4765 / Virus Database: 4015/8162 - Release Date: 09/05/14 > ------------------------------------------------------------------ > 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 forum is accessible at: > http://tech.groups.yahoo.com/group/si-list > > List archives are viewable at: > //www.freelists.org/archives/si-list > > Old (prior to June 6, 2001) list archives are viewable at: > http://www.qsl.net/wb6tpu > > > -- Steve Weir IPBLOX, LLC 1580 Grand Point Way MS 34689 Reno, NV 89523-9998 www.ipblox.com (775) 299-4236 Business (866) 675-4630 Toll-free (707) 780-1951 Fax All contents Copyright (c)2013 IPBLOX, LLC. All Rights Reserved. This e-mail may contain confidential material. If you are not the intended recipient, please destroy all records and notify the sender. ------------------------------------------------------------------ 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 forum is accessible at: http://tech.groups.yahoo.com/group/si-list List archives are viewable at: //www.freelists.org/archives/si-list Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu