Glad to make the measurements for you. Happy Holidays. Lee > [Original Message] > From: HINTON,MARK <mark.hinton@xxxxxxxxxxxxx> > To: <leeritchey@xxxxxxxxxxxxx> > Cc: si-list <si-list@xxxxxxxxxxxxx> > Date: 12/4/2007 4:56:02 AM > Subject: RE: [SI-LIST] Re: fiber-weave effect alive and well? > > My fabricator is in the US, and they said the 3313 was a special order > with an MOQ and higher cost. I've got a small qty, so this is not > appealing. They were shell-shocked at the idea of rotating artwork, but > happy to use specific glass weaves. > > It looks like we'll build this board with 2116 glass, and I'm hoping to > get a board to Lee for measurement in January. > > Mark > > -----Original Message----- > From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] > On Behalf Of Lee Ritchey > Sent: Monday, December 03, 2007 11:08 AM > To: Jeff Loyer > Cc: si-list > Subject: [SI-LIST] Re: fiber-weave effect alive and well? > > The correct designator for this weave is 3313 and it is not so hard to > get. > It's used all over Asia. I've build hundreds of boards in the US using > 3313. Isola makes a lot of this laminate and prepreg. > > One fabricator who has it in stock is Merix. They much prefer using > this > material to rotating images. I've copied John Stephens from Merix to > confirm this. > > Lee > > > > [Original Message] > > From: Loyer, Jeff <jeff.loyer@xxxxxxxxx> > > To: <leeritchey@xxxxxxxxxxxxx> > > Cc: si-list <si-list@xxxxxxxxxxxxx> > > Date: 12/3/2007 9:53:32 AM > > Subject: RE: [SI-LIST] Re: fiber-weave effect alive and well? > > > > As with everything, there are pros/cons to each. > > > > In his e-mail, Mark referred to a "special order 3113". That implies > > some challenges, perhaps including delivery delays, a limited supply > > base, and/or significant cost adder. > > > > Rotating the image would eliminate that problem, albeit with its own > > complications. > > > > Just suggesting an alternative; I don't know which is the most > > attractive for this particular application. > > > > Jeff Loyer > > > > -----Original Message----- > > From: Lee Ritchey [mailto:leeritchey@xxxxxxxxxxxxx] > > Sent: Monday, December 03, 2007 9:23 AM > > To: Loyer, Jeff; mark.hinton@xxxxxxxxxxxxx > > Cc: si-list > > Subject: RE: [SI-LIST] Re: fiber-weave effect alive and well? > > > > Why do that and make either CAD or Fab tougher when usinghte right > glass > > weave solved the problem nicely? > > > > Lee Ritchey > > > > > > > [Original Message] > > > From: Loyer, Jeff <jeff.loyer@xxxxxxxxx> > > > To: <mark.hinton@xxxxxxxxxxxxx> > > > Cc: si-list <si-list@xxxxxxxxxxxxx> > > > Date: 12/3/2007 9:02:02 AM > > > Subject: [SI-LIST] Re: fiber-weave effect alive and well? > > > > > > Mark, > > > For a low-volume test PCB, why don't you tweak the artwork 10 > degrees? > > > > > > Jeff Loyer > > > > > > -----Original Message----- > > > From: si-list-bounce@xxxxxxxxxxxxx > > [mailto:si-list-bounce@xxxxxxxxxxxxx] > > > On Behalf Of HINTON,MARK > > > Sent: Friday, November 30, 2007 2:48 PM > > > To: leeritchey@xxxxxxxxxxxxx > > > Cc: si-list > > > Subject: [SI-LIST] Re: fiber-weave effect alive and well? > > > > > > Lee, > > > > > > Have you tested 2116 glass yet? I'm doing a low-volume test PCB, > and > > I > > > may have to choose between 2116 or a high-cost special order of > 3113. > > > If you haven't tested it yet, would you venture an educated guess on > > how > > > it would perform? I've got pretty wide traces (9.5 mils). > > > > > > Thank you, > > > Mark > > > > > > > > > > > > -----Original Message----- > > > From: si-list-bounce@xxxxxxxxxxxxx > > [mailto:si-list-bounce@xxxxxxxxxxxxx] > > > On Behalf Of Lee Ritchey > > > Sent: Saturday, September 15, 2007 11:23 AM > > > To: Scott McMorrow; Perry.Qu@xxxxxxxxxxxxxxxxxx > > > Cc: si-list > > > Subject: [SI-LIST] Re: fiber-weave effect alive and well? > > > > > > The weave I document is 3313 glass. It is widely used in Asia and > is > > a > > > stock weave from Isola. We just completed testing on 2113 weave and > > > obtained similar results. The two thin weaves that are at the root > of > > > the > > > problem are 106 and 1080. 3313 has not been widely used by US > > > fabricators, > > > I suspect because designers have been asking for the thinnest > possible > > > laminates and that is why 1080 and 106 are used most often in the > US. > > > You > > > don't get 3313 and 2113 here unless you stick to your guns and > insist > > on > > > it. When you do, there are no real problems. > > > > > > We've just completed testing two designs with 48 ports of 10 GE with > > > superb > > > results. One used 2113 and the other 3313. > > > > > > 7628 is about as coarse as the cloth used to make levis. Not a good > > > choice. > > > > > > Lee > > > > > > > > > > [Original Message] > > > > From: Scott McMorrow <scott@xxxxxxxxxxxxx> > > > > To: <Perry.Qu@xxxxxxxxxxxxxxxxxx> > > > > Cc: si-list <si-list@xxxxxxxxxxxxx> > > > > Date: 9/14/2007 1:21:15 PM > > > > Subject: [SI-LIST] Re: fiber-weave effect alive and well? > > > > > > > > Perry > > > > Fiber-weave effects are alive and well, and IMO should be > considered > > > by=3D20 > > > > every designer concerned with 6 Gbps or higher differential serial > > > data=3D20 > > > > communications channels on PCBs, backplanes, and single-ended = > > > skew=3D20 > > > > controlled parallel buses. Jeff's paper is real life, building > > > upon=3D20 > > > > about 5 years of good research at Intel. The method that is used > > > is=3D20 > > > > quite valid and will be seen in real designs. The Intel research > > > is=3D20 > > > > able to better characterize weave skew using physical nyquist > > sampling > > > > > > > techniques. Yes, with different trace jogs you will see all sorts > > > of=3D20 > > > > potential alignments, but in the worst case you will still find > > > that=3D20 > > > > traces can have significant lengths of worst case fiber weave=3D20 > > > > alignment. If you are trying to design systems with 1000's > of=3D20 > > > > differential pairs, there is a statistical certainty that one or > > more > > > of=3D20 > > > > those pairs will have skew close to the absolute worst case, if = > > > not=3D20 > > > > designed to compensate for laminate weave anisotropy. > > > > > > > > The problem is most pronounced with weaves that have large holes > > > without=3D20 > > > > fiber in the weave pattern, but you will also see issues with = > > > core=3D20 > > > > materials that are often constructed with large diameter fibers, > > > like=3D20 > > > > 7628 material. The fiberglass the Lee proposes to use does have > > > some=3D20 > > > > benefits, however, it does not totally eliminate the fiber > > weave=3D20 > > > > problem. It reduces it to a lower level. Unfortunately, it is > not > > > a=3D20 > > > > widely manufactured laminate weave. > > > > > > > > There are patented techniques for improving weave-induced skew, > > > which=3D20 > > > > must be licensed. There are also some non-patented techniques, > > > which=3D20 > > > > may also be used that are not quite as effective as the > > patented=3D20 > > > > techniques, but nevertheless can be used to design robust systems. > = > > > =3D20 > > > > There is also some silicon IP that can be used to > automatically=3D20 > > > > compensate for skew, and is finding it's way into test > > > instrumentation. > > > > > > > > > > > > regards, > > > > > > > > Scott > > > > > > > > Scott McMorrow > > > > Teraspeed Consulting Group LLC > > > > 121 North River Drive > > > > Narragansett, RI 02882 > > > > (401) 284-1827 Business > > > > (401) 284-1840 Fax > > > > > > > > http://www.teraspeed.com > > > > > > > > Teraspeed(r) is the registered service mark of > > > > Teraspeed Consulting Group LLC > > > > > > > > > > > > > > > > QU Perry wrote: > > > > > I would be interested to see a link as well. > > > > > > > > > > Jeff's paper on DesignCon2007 is convincing to me that this is > > > something > > > > > we need to pay attention. Real life design will probably not be > as > > > bad > > > > > as the theoretical estimate since most of the diff pair routing > we > > > have > > > > > on the PCB is not likely to run a long length non-stop in > parallel > > > with > > > > > edge. The "jog" as is called in the paper is very common due to > > vias > > > etc > > > > > and pretty random. > > > > > > > > > > Also from the data we got from PCB vendor, it appears that > thinner > > > > > dielectric substrate the worse fibre weave effect as the gap > > between > > > the > > > > > fiber is larger. Has this been looked at ? > > > > > > > > > > Regards > > > > > > > > > > Perry > > > > > > > > > > > > > > > > =3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3 > > D= > > > 3D3D=3D3D3D=3D3D3D=3D3D3D=3D3 > > > D=3D > > > 3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D > > > =3D3D3D=3D3D > > > > > =3D > > > > > > =3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3 > > D= > > > 3D3D=3D3D3D=3D3D3D=3D3D3D=3D3 > > > D=3D > > > 20 > > > > > > > > > > Perry Qu=3D3D20 > > > > > > > > > > Design & Qualification, Alcatel-Lucent Canada Inc. > > > > > > > > > > 600 March Road, Ottawa ON, K2K 2E6, Canada=3D3D20 > > > > > > > > > > DID: 613-7846720 Fax: 613-5993642=3D3D20 > > > > > > > > > > Email: perry.qu@xxxxxxxxxxxxxxxxxx=3D3D20 > > > > > > > > > > > > > > > > =3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3 > > D= > > > 3D3D=3D3D3D=3D3D3D=3D3D3D=3D3 > > > D=3D > > > 3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D > > > =3D3D3D=3D3D > > > > > =3D > > > > > > =3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3D3D3D=3 > > D= > > > 3D3D=3D3D3D=3D3D3D=3D3D3D=3D3 > > > D=3D > > > 20 > > > > > > > > > > =3D3D20 > > > > > > > > > > =3D20 > > > > >> -----Original Message----- > > > > >> From: si-list-bounce@xxxxxxxxxxxxx=3D3D20 > > > > >> [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of=3D3D20 > > > > >> Aubrey_Sparkman@xxxxxxxx > > > > >> Sent: Friday, September 14, 2007 1:59 PM > > > > >> To: leeritchey@xxxxxxxxxxxxx; rdudek@xxxxxxxxxxxxxxx;=3D3D20 > > > > >> si-list@xxxxxxxxxxxxx > > > > >> Subject: [SI-LIST] Re: fiber-weave effect alive and well? > > > > >> =3D3D20 > > > > >> Would you like to share a link?=3D3D3D20 > > > > >> =3D3D20 > > > > >> =3D3D20 > > > > >> Aubrey Sparkman=3D3D3D20 > > > > >> Enterprise Engineering Signal Integrity Team=3D3D3D20 Dell, > > > Inc.=3D3D3D20=3D3D20 > > > > >> Aubrey_Sparkman@xxxxxxxx=3D3D3D20 > > > > >> (512) 723-3592=3D3D3D20 > > > > >> "Discovery consists of seeing what everybody has seen > and=3D3D20 > > > > >> thinking what nobody else has thought." - Jonathan Swift > > > > >> =3D3D20 > > > > >> =3D3D20 > > > > >> -----Original Message----- > > > > >> From: si-list-bounce@xxxxxxxxxxxxx=3D3D20 > > > > >> [mailto:si-list-bounce@xxxxxxxxxxxxx] > > > > >> On Behalf Of Lee Ritchey > > > > >> Sent: Friday, September 14, 2007 11:36 AM > > > > >> To: Russell S. Dudek Jr.; si-list@xxxxxxxxxxxxx > > > > >> Subject: [SI-LIST] Re: fiber-weave effect alive and well? > > > > >> =3D3D20 > > > > >> We already have a glass weave solution. Check my column > > in=3D3D20 > > > > >> the April issue of Circuitree magazine. > > > > >> =3D3D20 > > > > >> Lee Ritchey > > > > >> =3D3D20 > > > > >> =3D3D20 > > > > >> =3D20 > > > > >>> [Original Message] > > > > >>> From: Russell S. Dudek Jr. <rdudek@xxxxxxxxxxxxxxx> > > > > >>> To: <si-list@xxxxxxxxxxxxx> > > > > >>> Date: 9/12/2007 1:10:28 PM > > > > >>> Subject: [SI-LIST] Re: fiber-weave effect alive and well? > > > > >>> > > > > >>> Steve, > > > > >>> =3D3D3D20 > > > > >>> I agree, Fiber Weave Effect (FEW) has most certainly > been=3D3D20 > > > > >>> =3D20 > > > > >> confirmed by > > > > >> such > > > > >> =3D20 > > > > >>> research. However, there is a new change in the wind. > I=3D3D20 > > > > >>> =3D20 > > > > >> have the=3D3D3D20=3D3D20 > > > > >> =3D20 > > > > >>> unique opportunity, as a technical liaison, to enable a=3D3D20 > > > > >>> =3D20 > > > > >> technology=3D3D3D20=3D3D20 > > > > >> =3D20 > > > > >>> that may put > > > > >>> =3D20 > > > > >> an > > > > >> =3D20 > > > > >>> end to FWE as a consideration in high-speed designs. > We=3D3D20 > > > > >>> =3D20 > > > > >> all know that > > > > >> =3D3D20 > > > > >> =3D20 > > > > >>> the crux of the matter is the glass weave and its effect > > on=3D3D20 > > > > >>> =3D20 > > > > >> localized > > > > >> Er. > > > > >> =3D20 > > > > >>> Either get ride of the reinforcement layer completely or > > > more=3D3D3D20=3D3D20 > > > > >>> challenging change the fundamentals of the glass weave > > fabrication > > > > >>> =3D20 > > > > >> process (GWFP). > > > > >> =3D20 > > > > >>> =3D3D3D20 > > > > >>> We have taken the more challenging (and fun) approach and =3D > > > have=3D3D20 > > > > >>> rocked=3D3D3D20 the fundamentals the GWFP. I cannot disclose > > much > > > the=3D3D20 > > > > >>> specifics of=3D3D3D20 the technology and our partners in such > > =3D > > > an=3D3D20 > > > > >>> =3D20 > > > > >> open forum. =3D3D20 > > > > >> =3D20 > > > > >>> However, if=3D3D3D20 you are interested learning more feel = > > > free=3D3D20 > > > > >>> =3D20 > > > > >> to contact=3D3D20 > > > > >> =3D20 > > > > >>> me and we can=3D3D3D20 get the proper NDAs in place to =3D > > > facilitate=3D3D20 > > > > >>> =3D20 > > > > >> such a discussion. > > > > >> =3D20 > > > > >>> =3D3D3D20 > > > > >>> RD > > > > >>> =3D3D3D20 > > > > >>> Russell Dudek > > > > >>> Technology Specialist > > > > >>> Compunetics, Inc. > > > > >>> 700 Seco Road > > > > >>> Monroeville, PA 15146 > > > > >>> 412-858-6264 > > > > >>> rdudek@xxxxxxxxxxxxxxx > > > > >>> www.compunetics.com <http://www.compunetics.com/> =3D3D3D20 > > > > >>> > > > > >>> To see where no one notices the contrast of white on white is > = > > > =3D3D > > > > >>> =3D20 > > > > > an=3D3D3D20=3D3D20 > > > > > =3D20 > > > > >>> indispensable virtue of infinite potential. > > > > >>> > > > > >>> =3D3D3D20 > > > > >>> > > > > >>> > > > > >>> > > > > >>> > > ------------------------------------------------------------------ > > > > >>> To unsubscribe from si-list: > > > > >>> si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the=3D3D20 > > > > >>> =3D20 > > > > >> Subject field > > > > >> =3D20 > > > > >>> 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 technical documents are available at: > > > > >>> http://www.si-list.net > > > > >>> > > > > >>> List archives are viewable at: =3D3D3D20 > > > > >>> //www.freelists.org/archives/si-list > > > > >>> or at our remote archives: > > > > >>> http://groups.yahoo.com/group/si-list/messages > > > > >>> Old (prior to 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//www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net 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