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