R: [SI-LIST] : Serpentine traces

g.rossi@crf.it
Fri, 24 Apr 1998 09:02:00 +0200

What is double back ?

thank you=20
g.rossi

> ----------
> Da: D. C. Sessions[SMTP:dc.sessions@tempe.vlsi.com]
> Inviato: gioved=EC 23 aprile 1998 21.10
> A: si-list@silab.Eng.Sun.COM
> Oggetto: Re: [SI-LIST] : Serpentine traces
>=20
> Paul Thompson wrote:
> >=20
> > >Has anyone ever tried to simulate the effect of serpentine coupled
> lines in
> > >SPICE?
>=20
> > I have a related question: Let's say you have a big wide bus and you
> want
> > to match the lengths of all the traces. Trying to put wide spacing
> between
> > all the serpentine traces would obviously require lots of layers. As=
an
> > alternative, what do people think of routing the "doubled-back" secti=
ons
> > all on a different layer, preferably one on the opposite side of the
> same
> > plane that the "main" traces are run? I'm assuming here that the ent=
ire
> > bus switches at the same time.
>=20
> Layer-to-layer manufacturing mismatch is pretty fierce, and then there
> are the vias. Seems to me that getting the delays matched is going
> to be a LOT of work, and will never be as consistent in manufacture
> as double-back would be.
>=20
> --=20
> D. C. Sessions
> dc.sessions@tempe.vlsi.com
>=20