I have been using the Autorouter it it works quite well - Maximize the via
numbers (why limit this) and set up your preferences and let it rip.
I then go back and pretty up the traces - then it is done.
I am working on a more complex board which will give it a good test.
Anyone else with experience with this tool who would comment on do's and
don'ts?
Don
"Harald Kipp" <eagle@egnite.de> wrote in message
news:fhf112$i1$1@cheetah.cadsoft.de...
Mark Lucia schrieb:
With some larger projects, I'll run the auto router with all optimization turned off, simply to get a feel for part placement.
With some larger projects, I'll run the auto router with all optimization
turned off, simply to get a feel for part placement.
I'm doing this sometimes as well.
I found that if I then enable the optimizers, and run the auto router once again, nothing changes - I suspect because the auto router no longer knows about the vias - (shows VIAS: 0)
I found that if I then enable the optimizers, and run the auto router
once again, nothing changes - I suspect because the auto router no longer
knows about the vias - (shows VIAS: 0)
Not sure, if I understood this correctly. AFAIK, the autorouter will not touch any trace, which had been routed already. It will route airwires only. Harald
Not sure, if I understood this correctly. AFAIK, the autorouter will not
touch any trace, which had been routed already. It will route airwires
only.
Harald
Don Golding wrote:
I have been using the Autorouter it it works quite well - Maximize the via numbers (why limit this) and set up your preferences and let it rip.
Are you serious ??
for high speed or low noise design routing is critical, and this
includes what side the tracks are on, and where the vias are
Numerous vias can also affect reliability, manufacturabilty, EMC.
Most of my design fall into this category, in which case the autorouter
is very poor. Personally I never use it.
In general low cost autorouters are appropraite for moderate speed
digital designs on a minimum of 4 layers. New users should first learn
to appreciate the importance of current flow in the layout before
considering touching the autorouter.
Anything else should pretty much be routed by hand.
Too often the autorouter just encourages lazy routing and too many
newbies use it and don't understand the importance of return current
flow in design of optimum PCB layout.
In which case my main comment is do not use the autorouter for single or
two layer designs.
cheers
David
I agree with you your observations!
All speed sensitive or impedance critical routes should be done by hand -
first. Route the clock, impedance matched lines, power traces first by
hand.
I use it on four layer boards typically and rarely go above 50mhz digital
designs. I do alot of low frequency analog and motor control, embedded
processor stuff which is not layout critical. typically.
Use the right tool for the right job. I move things around a little bit
after it is done - I think the most offensive thing the autorouter produces
is more vias, which I don't think is a big deal today, and it is very useful
for lower speed designs and complex IO type of stuff.
On the other hand, it is pretty fexible and it doesn't seam to put many
crazy routes around the board. For the price, it is very good....
"David" <david@nospam.com> wrote in message
news:fo23bf$be5$1@cheetah.cadsoft.de...
I have been using the Autorouter it it works quite well - Maximize the
via numbers (why limit this) and set up your preferences and let it rip.
Are you serious ?? for high speed or low noise design routing is critical, and this includes what side the tracks are on, and where the vias are Numerous vias can also affect reliability, manufacturabilty, EMC. Most of my design fall into this category, in which case the autorouter is very poor. Personally I never use it. In general low cost autorouters are appropraite for moderate speed digital designs on a minimum of 4 layers. New users should first learn to appreciate the importance of current flow in the layout before considering touching the autorouter. Anything else should pretty much be routed by hand.Too often the autorouter just encourages lazy routing and too many newbies use it and don't understand the importance of return current flow in design of optimum PCB layout. In which case my main comment is do not use the autorouter for single or two layer designs. cheers David
for high speed or low noise design routing is critical, and this includes
what side the tracks are on, and where the vias are
Most of my design fall into this category, in which case the autorouter is
very poor. Personally I never use it.
In general low cost autorouters are appropraite for moderate speed digital
designs on a minimum of 4 layers. New users should first learn to
appreciate the importance of current flow in the layout before considering
touching the autorouter.
Too often the autorouter just encourages lazy routing and too many newbies
use it and don't understand the importance of return current flow in
design of optimum PCB layout.
