Hi, Steve Thank you I use SI wave and HFSS simulation software Which one is better for this vias in the 25Gbps application? Do you agree P/N share only one stitching vias with the same return path is good? Thank you Lee > steve weir <weirsi@xxxxxxxxxx> 於 2014/9/6 下午7:42 寫道: > > "It depends". In the general sense: Tighter stitching increases the > lowest cavity resonant frequencies. However stitching is not free, and > where stitching goes particularly close to signal vias can have a big > impact on how the overall structure performs. > > If you want well controlled results that meet a particular loss budget, > then you really need to model in a good solver. You can always contract > with someone to design your transitions for you. There are entire > businesses built around getting structures like this right: Teraspeed, > Wild River, etc. > > Steve >> On 9/6/2014 4:25 AM, Leeyuyun wrote: >> 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 >> >> >> > > > -- > 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 > > ------------------------------------------------------------------ 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