> Serious question. In what professional (or not) setting would one
> seriously use an autorouter for designing PCBs?
>=20
> No sarcasm intended. I have tried a few but have always found that it's
> best done manually. But it seems that CAD tool companies spend a
> significant amount of time developing their autorouters.
>=20
> Is there any serious use for them?

The biggest hassle with an autorouter is to make sure you have ALL the rule=
s set properly before you start, as in minimum signal track width, minimum =
power bus widths, minimum via size, minimum track spacing, the list just go=
es on and on.=20

When I look at the numerous options available in the Allegro/PCB Editor pac=
kage we use with OrCad the myriad constraint options that can be set up are=
 truly mind boggling.

Then once these are properly set up, the autorouter will start to make some=
 sense of doing a layout. Bear in mind that (in my experience anyway) for a=
 given track it will always use the minimum track width, minimum via size a=
nd minimum track spacing, which results in some "why the heck did it do tha=
t!" comments. Examples are the way it will zigzag a track alongside a bunch=
 of others instead of doing a long x track then a long y track (assuming th=
e space is available) but the autorouter doesn't see a problem because the =
Manhattan distance is the same.
--=20
Scanned by iCritical.

--=20
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