[SI-LIST] Re: 6 layers stackup
- From: "Bowden, Ivor" <ibowden@xxxxxxxxxxxxxxxxx>
- To: "Dave Pollum" <vze24h5m@xxxxxxxxxxx>, "Fernando Yuitiro Mori" <mori@xxxxxxxxxxxxx>
- Date: Fri, 22 Feb 2008 06:50:47 -0800
-----Original=20Message-----
From:=20si-list-bounce@xxxxxxxxxxxxx=20[mailto:si-list-bounce@xxxxxxxxxxxx=
g]
On=20Behalf=20Of=20Dave=20Pollum
Sent:=20Thursday,=20February=2021,=202008=203:11=20PM
To:=20Fernando=20Yuitiro=20Mori
Cc:=20si-list@xxxxxxxxxxxxx
Subject:=20[SI-LIST]=20Re:=206=20layers=20stackup
Fernando=20Yuitiro=20Mori=20wrote:
>=20Hi,
>=20I=20normally=20use=20S1=20S2=20G=20P=20S3=20S4=20for=20the=206=20layer=
s=20stackup.=20I=20need=20the=204=20
>=20layer=20with=2060=20ohms,=20so=20there=20are=20some=20problem=20if=20I=
=20use=20S1=20G=20S2=20S3=20P
S4?
>=20Regards,
>
>=20Fernando=20Mori
>=20=20
>
With=20a=20"S1=20G=20S2=20S3=20P=20S4"=20stackup,=20you=20won't=20get=20th=
e=20helpful=20capacitance=20
between=20the=20Power=20and=20Ground=20planes=20because=20to=20planes=20ar=
e=20too=20far=20away.
In=20Lee=20Ritchie's=20book=20"Right=20the=20First=20Time=20-=20A=20Practi=
cal=20Handbook=20on=20
High=20Speed=20PCB=20and=20System=20Design,=20Volume=202"=20he=20discusses=
=20a=20similar=20
problem=20with=20a=206=20layer=20board=20(pg.=2043).=20=20That=20board=20w=
as=20flaky=20and=20failed=20
EMI=20testing.=20=20His=20solution=20was=20to=20copper=20flood=20all=20non=
-used=20board=20area=20
on=20each=20_signal_=20layer,=20and=20then=20connect=20the=20flooded=20cop=
per=20to=20the=20
appropriate=20power=20or=20ground=20plane.=20=20In=20your=20case,=20layers=
=20S1=20and=20S2=20are=20
adjacent=20to=20the=20Ground=20plane,=20so=20the=20copper=20flood=20on=20t=
hose=20layers=20must=20
be=20connected=20to=20the=20_power_=20plane.=20=20Layers=20S3=20and=20S4=20=
are=20adjacent=20to=20the
Power=20plane,=20so=20the=20copper=20flood=20on=20these=20layers=20must=20=
be=20connected=20to=20
the=20_ground_=20plane.=20=20Make=20sure=20that=20there=20are=20"enough"=20=
vias=20to=20connect=20
the=20floods=20to=20the=20appropriate=20plane.
HTH
-Dave=20Pollum
Dave,=20Fernando,
When=20flooding=20signal=20planes=20with=20power=20nets=20one=20must=20be=20=
careful=20what
effect=20it=20has=20on=20the=20impedance=20of=20traces=20on=20the=20adjace=
nt=20signal=20layer,
as=20it=20essentially=20reduces=20the=20stack=20up=20from=20P-S-S-P=20to=20=
P-S-P=20in=20selected
areas.
-Ivor
_______________________________________________________________________
This=20e-mail=20and=20any=20files=20transmitted=20with=20it=20are=20propri=
etary=20and=20intended=20solely=20for=20the=20use=20of=20the=20individual=20=
or=20entity=20to=20whom=20they=20are=20addressed.=20If=20you=20have=20reas=
on=20to=20believe=20that=20you=20have=20received=20this=20e-mail=20in=20er=
ror,=20please=20notify=20the=20sender=20and=20destroy=20this=20email=20and=
=20any=20attached=20files.=20Please=20note=20that=20any=20views=20or=20opi=
nions=20presented=20in=20this=20e-mail=20are=20solely=20those=20of=20the=20=
author=20and=20do=20not=20necessarily=20represent=20those=20of=20the=20Cur=
tiss-Wright=20Corporation=20or=20any=20of=20its=20subsidiaries.=20=20Docum=
ents=20attached=20hereto=20may=20contain=20technology=20subject=20to=20gov=
ernment=20export=20regulations.=20Recipient=20is=20solely=20responsible=20=
for=20ensuring=20that=20any=20re-export,=20transfer=20or=20disclosure=20of=
=20this=20information=20is=20in=20accordance=20with=20applicable=20governm=
ent=20export=20regulations.=20=20The=20recipient=20should=20check=20this=20=
e-mail=20and=20any=20attachments=20for=20the=20presence=20of=20viruses.=20=
Curtiss-Wright=20Corporation=20and=20its=20subsidiaries=20accept=20no=20li=
ability=20for=20any=20damage=20caused=20by=20any=20virus=20transmitted=20b=
y=20this=20e-mail.
------------------------------------------------------------------
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 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
Other related posts:
