PCB layout from schematic?

[gez]

How well do PCB programs transfer a schematic into finished artwork at the click of a mouse?

I downloaded Proteus Lite (Ares) for evaluation and it’s fairly intuitive.  For the PCB programme on its own it doesn’t cost much, but if I wanted the option of creating a layout automatically from a schematic,  I’d probably be better off buying different software (would work out cheaper).  

Do most of you, like myself, just do your layouts from scratch, or is the extra ‘automatic layout’ option worth the extra expense?  Do you get some control of how the layout is arranged (e.g. size of board or placement of PCB mount pots), or do you just have to accept what it throws out at you and edit it afterwards?  If so, is the amount of time you spend editing worth it?

[Nasse]

I buyed Proteus Lite licence maybe two years ago. I tried few small things with free demo version. I reached the upper limit of components/traces in some trial project and there maybe was some bugs in the demo version, it crashed sometimes annoyingly when editing. The unlimited version worked solid, no crashes. Been too lazy and busy with my day job so it has been resting for long time  :oops: ...

But quess learning to use this kind of programs is difficult for starters, and you must do quite a job to reach certain level. I quess I mostly do single sided stuff if I´ll do anything, and just simple well-working autorouter would be good for me.

[bobbletrox]

There are programs that do all that for you?!?!  And here I've been doing them all by hand  :evil:

[Paul Perry (Frostwave)]

Believe me, you are better doing analog layout by hand.
Get RG's book (I did!).
Protel etc are OK for actually doing the artwork, but for routing analog, unfortunately there is no substitute for knowing what you arte di\oing. I had an engineer use auto layout for a ring modulator, I had to do the board again. He's working for the Defence Dept now, lord help us! :shock:

[BILLYL]

I agree with Paul - Get RG's book (I did) and work it out by hand.  These circuits are not that complex and what you will find you can noodle it through with your mind.  And I find that to be most of the fun.........

Good Luck

BILL

[gez]

I've been making PCBs since day one and so far, touch wood, every single layout has worked for me.  I just wanted to know how good auto layout is on these programs (not just Proteus).  Although I too find it fun plotting it all out, it can be a little time consuming.  Is there a sort of 'halfway house' where you can instruct the program to place certain components where you want them, and use certain size taces for power etc?

I'll probably end up just going for the layout part of Proteus, but I'm still curious about these new-fangled auto layout thingies...

[Nasse]

:roll: I only autorouted some digital stuff, and when doing some audio stuff, I first did basic part placement and star-grounding-trial by hand...

OK you are right, the program did not do the hard brain-work for me...

[R.G.]

I'm still curious about these new-fangled auto layout thingies...

I took my first class in design layout and automation in 1978. The mantra at that time was "get autorouting to work for digital, some day we'll get analog routing to work". Near as I can tell, it still is.

The net result is that analog autorouting can produce things that will be electrically connected correctly, but it cannot touch the efficiency of layout of a human mind (yet, at least) and cannot take into account the myriad analog considerations that matter particularly in high gain, mismatched impedance audio circuits. Some day, but not yet, and certainly not in free or low cost software packages.

Take your gloves off, get in there and do it by hand.

[gez]

Take your gloves off, get in there and do it by hand.

Fair enough.  I just wanted to be sure it wasn't a false economy my only going for the layout bit of the software. I'd hate to find out later down the line that autorouting is the 'dog's doo dahs' and that I could have saved myself a lot of time for just a 'little' extra cost.

Always best to ask when in doubt!  

[Gilles C]

Just my 2 cents...

I still like to use Eagle to do my layouts.

The main advantage, at least for me, is that it permits me not to forget any traces. Even if I am not using the autorouter, I find it nice to have all the parts connected together as per the schematic, even if I have to trace the layout myself.

I can come back on a layout after a while and still see the traces that are still done. Or I can modify a schematic and just modify the original pcb layout to fit the changes.

[gtrmac]

As far as I can tell autorouting makes a mess out of things. I have Protel 99SE but when I've tried autorouting it was a waste of time.

[mikeb]

Consider the game of chess - it's a very well understood system with a finite number of very precise rules. Even still, it takes a hell of a good piece of software AND fast hardware to get close to the best human players. Examining PCB layout from a generic point of view (i.e. not digital or analog - FX circuits, say - specifically), you'd think that surely this problem would be easier to solve than the 'play winning game of chess problem' - maybe it's just that not enough money has been thrown at the solution? Again, similar to the way chess players have certain styles of play, analog PCB layout people often have a 'style' of their own. Look at RGs layouts, for example - you can recognise his efforts very often immediately. Also, FP from tonepad - his 'style' is also very distinctive. How people tackle and solve 'pure' mental problems like this can be very fascinating!

Personally, I quite enjoy - still - doing PCB layouts.

Mike

[Paul Marossy]

I tried Eagle for one or two circuits and gave up on it. It's a lot easier for me to just design a PCB from scratch, I get exactly what I want and I like the challenge of doing that, too.

[keko]

Is there a software like Eagle, or even Express PCB that runs on a Mac?

I recently switched platforms, and one of the things I regret the most is loosing Xpress PCB.

I just downloaded one called Osmond X, but it doesn't cut it at all.

[niftydog]

there are, but they ain't cheap... no free demos that I've found yet.

McCad is one.

[Gringo]

I'm about to move to linux (debian), and i'm still looking for something like ExpressPcb. I've tried Eagle, but it's way too complex for what i want.

Any takers other than Eagle and PCB for linux?