Hi Ismail, This is simply "added copper" to the outer board layers to ensure a consistant plating thickness across the surface of the boards. This is generally added by the fabrication house, without cost, to provide them better quality. Generally there is no problems associated with the practice, as long as the fab shop has guidance regarding how close to "features" they can get, but there are some times issues. This is definitely NOT a practice for RF designs. Good day. Mitch ---------Included Message---------- > Date: Tue, 02 Jul 2002 09:17:28 -0400 > From: "Alex McPheeters" <amcpheeters@xxxxxxxx> > Reply-To: <amcpheeters@xxxxxxxx> > To: <ismailb@xxxxxxxxxxxxxxx>, "si-list" <si-list@xxxxxxxxxxxxx> > Subject: [SI-LIST] Re: Rectangular patterns on Toplayer. > > > I'm not going near this with a 10' pole! > > > At 06:26 PM 7/2/02 +0530, Ismail B - CTD, Chennai. wrote: > > > >Hello guys, > > > >I don't know whether this question has any relevance to signal integrity. > >But In some boards I see islands of copper (like rectangular patterns) on > >the top layer. I just wonder why this kind of pattern is used. Is it any > >thing to deal with EMI or what??? > > > >Thanks a ton, > >Ismail > > > > > >------------------------------------------------------------------ > >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 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 > > > > Alex McPheeters > Vice President, Business Development > American Computer Development Inc. > Office - (301) 620-0900 > Fax - (301) 620-9099 > Cell - (301) 305-3051 > > "The secret of success is constancy of purpose." > Benjamin Disraeli (1804 - 1881) > > > > ------------------------------------------------------------------ > 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 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 > > > ---------End of Included Message---------- _____________________________________________________________ ------------------------------------------------------------------ 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 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