Routing techniques

[Attila]

I am interested in the PCB routing techniques. I've recently made a simple PCB with Eagle. The autorouter could not finish the board with only one layer, so I went to do it myself. I ended up with 11 bridges. Here is it:

Is there any possible solution to reduce or eliminate the bridges? I would send the Eagle project file.

Is there any better program that has a better autorouter?

[Skunk]

I'd try to turn the ICs and move the JPs. It might need two or three trials. Such a simple design should be possible without bridges...

Cheers,

Skunk

[Attila]

I tried it before posting this whole thing. The autorouter always failed at 70-80% (depending on the parts placement), so I sat down and routed the PCB myself. JP1-JP8 are close as possible to their IC pins.

BTW: do you know, what's this?

[Jidis]

Attila,

Don't know if it was the right thing to do,  but I've sort of moved away from the autorouter. I've also gotten in a habit of cramming way too much stuff onto small boards, so that may be one of the reasons. ;D

If you start with a blank board (I actually keep my prefs on black/colors on a white background), then zoom out a ways, and drag your wired up components out into the free space, spreading them apart some, you can usually see the individual airwires a little better. Afterward, you can drag them each around the space with the move tool, right clicking as needed to rotate them, and you should see an arrangement which will get you the least amount of criss-crossed wires. Then you can bring them in closer and arrange them on the board. I usually just start manually laying routes after that, but if you've moved them around like that, the autorouter may have better luck. Doesn't look like you've got but one "normal" passive component on there, but the usual resistors and crap can be a big help for stepping overtop of some traces.

An option to color the different airwires in Eagle may have made all that a bit easier. I sometimes will temporarily switch to a brightly colored layer and lay a simple temporary route for one of my longer wires, just so I can see what it's likely to crash into, while I'm laying the other ones.

BTW- If you haven't found this already, the rotate tool can do weird angles, if you click on an object, and drag outside it's center.

Also, if you can manage to ride between a few IC pins on some of the routes, you may save yourself a few jumpers.

Have Fun,

George

PS- Couldn't help but wonder.. what does that circuit do?     

[moebius]

Autorouters are No good! (Ok, maybe then when you have 4 layer board with separate power and Ground planes and lotsa Bus architecture stuff)

I do use autorouter for "drafting" - or I make loose functional blocks out of different parts of the circuits and then use autorouter to see how good different layout versions SEEM to be routable.

I had a five min look at that board and used my "eye vision router" and came to the conclusion that board doesn't need a single bridge even with the current IC positioning 8)

Remember it's a puzzle You have to solve!

Moebius

[Attila]

OK, so I'm the dumb ;D

Anyway, I came up with a new design, and I have only 9 bridges on it and it will fit better in my amp (first clue to my question).

Is it better?

[stryd_one]

Just at a glance, looks like that bottom IC could get turned 90 degrees clockwise ?