Thanks for your help! It's appreciated. Have a nice day! Marc-André Filion, ing Concepteur Matériel / Hardware Designer Brioconcept Consulting Inc. 450.681.2779 x2368 -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of steve weir Sent: 4 février 2013 08:48 To: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: Loose coupling vs tight at the same time Marc, using practical geometries the line to line coupling of the most tightly coupled differential pair on a PCB with an image plane is less than 15%. Steve On 2/4/2013 4:04 AM, Marc-André Filion wrote: > Hi, > Does the coupling type (tight and loose) affect the way that the return > current will behave? Someone told me that a tight coupled diff pair return > current will be more on the coupled trace than the reference plane. Since the > coupling is stronger with the other trace, the electron will tend to flow on > the trace rather than on the plane. > > I'm really not sure about this one, but the doubt is high enough to check how > urban this legend is. > > Regards, > > > > Marc-André Filion, ing > Concepteur Matériel / Hardware Designer Brioconcept Consulting Inc. > 450.681.2779 x2368 > > > -----Original Message----- > From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On > Behalf Of steve weir > Sent: 1 février 2013 20:27 > To: si-list@xxxxxxxxxxxxx > Subject: [SI-LIST] Re: Loose coupling vs tight at the same time > > Marc, just to add a little bit to Lee's good comment: The impedance in > both even and odd modes is going to change. How much this is going to > cause S11 impairment depends on just how tightly you couple in the pin field. > If the data rate is reasonably high I encourage you to put what you are > considering through a field solver so that you can see what is going to > happen to both your reflections and your cross talk. The latter may be the > bigger problem with what you are trying to do. > > > Steve. > On 2/1/2013 3:33 PM, Lee wrote: >> The big thing to worry about is the change in impedance when you go >> from tight to loose or the reverse. Any good 2D field solver will >> allow you to quantify that. >> >> -----Original Message----- >> From: Marc-André Filion >> Sent: Friday, February 01, 2013 2:35 PM >> To: SI-LIST mailing list >> Subject: [SI-LIST] Loose coupling vs tight at the same time >> >> Hi, >> We’re having a discussion here and I would like to know your thought >> about it. >> >> How bad is it to transition from tight coupling diff signal to loose >> coupling signal and vice-versa. We have a case here where we pass-thru >> a pin field and we reduce the coupling from loose to tight for 2”and >> get back to loose after. >> >> >> >> I’m not sure that it’s a good approach. What’s your idea on this? >> >> >> >> >> >> >> >> Marc-André Filion >> >> >> ------------------------------------------------------------------ >> 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: 2013.0.2897 / Virus Database: 2639/6074 - Release Date: >> 02/01/13 >> >> ------------------------------------------------------------------ >> 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)2012 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 > > > -- 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)2012 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