[SI-LIST] Re: pcb stackup

Bingo, it's tough to meet these requirements economically on a 6-layer board!

Doug




At 01:28 PM 6/19/2003 -0700, Virendra wrote:
>Doug, how would you propose to get good planer
>capacitance in a 6 layer board, i have a constraint of
>overall thickness of 0.062 inches.
>thanks in advance,
>
>virendra
>
>--- Doug Brooks <doug@xxxxxxxxxx> wrote:
> > I also second Matt.
> >
> > A good stackup (from a signal integrity standpoint)
> > meets BOTH of these
> > conditions:
> >
> > 1. Every trace layer is referenced to a plane
> > 2. There is at least one power/ground plane pair
> > (per power supply)
> > (closely coupled, providing good planar capacitance
> > between)
> >
> > (Rick Hartley wrote a good article about this in the
> > July, 2000, issue of
> > Printed Circuit Design)
> >
> > You need point one for:
> > loop area control (EMI)
> > crosstalk control
> > impedance control
> >
> > You need point two for:
> > high speed decoupling
> > common mode control (EMI)
> >
> >
> > Pardon the adv, but I have a new book out that
> > covers all these points
> > ISBN  0-13-141884-X
> >
> > Doug Brooks
> >
> >
> >
> >
> > At 09:56 AM 6/18/2003 -0400, you wrote:
> > >a typical stackup at our company might look like
> > this:
> > >
> > >1) G
> > >2) S
> > >3) S
> > >4) +3.3V
> > >5) S
> > >6) S
> > >7) G
> > >8) S
> > >9) S
> > >10)G
> > >
> > >note that we use layer 4 (+3.3V) as a reference
> > plane.
> > >
> > >an alternate stackup is now being pushed here that
> > doesn't allow this.
> > >the alternative approach says that this puts too
> > much noise in the +3.3V
> > >plane.
> > >that we should surround the +3.3V plane with ground
> > planes, as shown below :
> > >1) G
> > >2) S
> > >3) S
> > >4) G
> > >5) +3.3
> > >6) G
> > >7) S
> > >8) S
> > >9) G
> > >10)S
> > >11)S
> > >12)G
> > >
> > >Comments?
> > >
> > >thanks,
> > >Jim Peterson
> > >Honeywell
> >
> >------------------------------------------------------------------
> > >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:
> > >http://www.freelists.org/webpage/si-list
> > >
> > >For help:
> > >si-list-request@xxxxxxxxxxxxx with 'help' in the
> > Subject field
> > >
> > >List archives are viewable at:
> > >
> > http://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
> > >
> >
> >
>_______________________________________________________________________________
> >
> >
> >
>------------------------------------------------------------------
> > 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:
> > http://www.freelists.org/webpage/si-list
> >
> > For help:
> > si-list-request@xxxxxxxxxxxxx with 'help' in the
> > Subject field
> >
> > List archives are viewable at:
> >               http://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
> >
> >
>
>
>__________________________________
>Do you Yahoo!?
>SBC Yahoo! DSL - Now only $29.95 per month!
>http://sbc.yahoo.com
>------------------------------------------------------------------
>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:
>http://www.freelists.org/webpage/si-list
>
>For help:
>si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
>
>List archives are viewable at:
>                 http://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
>

_______________________________________________________________________________


------------------------------------------------------------------
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:
http://www.freelists.org/webpage/si-list

For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field

List archives are viewable at:     
                http://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: