To minimize your radiation you may want to=20 1) ensure you have a low impedance power plane 2) be careful about shielding any cable grounds to your faraday case=20 "gnd". To get a low impedance power plane you may want to consider having full planes power planes, and a good decoupling strategy. Also separation of ground plane to power plane plays a major role in reducing power plane impedance. Use the minimum prepreg size that can be supported for volume production. As for cables that is a whole different story and I don't think it is relevant to your situation. Nima Lotfi > -----Original Message----- > From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] > Sent: Monday, February 21, 2005 3:03 PM > To: si-list@xxxxxxxxxxxxx > Subject: [SI-LIST] PCB stackup >=20 >=20 > Hi all, >=20 > I am working on a product which requires high shielding (no > interference with mobile pagers) and the PCB goes in plastic > enclosure (w/o metallic paint). The highest working frequency is > 200Mhz and the PCB stackup is : >=20 > TOP ground > Layer1 signal + power fill 1.8V > Layer2 ground > Layer3 signal + power fill 3.3V > Layer 4 signal + power fill 5V > Layer 5 ground > Layer 6 signal + power fill 3.3V > Bottom ground >=20 >=20 > Is this stackup ok? and do you think that not having a full power > plane would be a problem? >=20 >=20 > thanks >=20 >=20 >=20 > ------------------------------------------------------------------ > To unsubscribe from si-list: > si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field >=20 > or to administer your membership from a web page, go to: > //www.freelists.org/webpage/si-list >=20 > For help: > si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field >=20 > List FAQ wiki page is located at: > http://si-list.org/wiki/wiki.pl?Si-List_FAQ >=20 > List technical documents are available at: > http://www.si-list.org >=20 > 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 >=20 >=20 ------------------------------------------------------------------ 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 FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org 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