PCB Designing tutorial

Strange site. Tries to sell something, ... AVR devkit 1499 ??, what curreny ? Tried to lookup the place ... There is no place and no country.

Rene

Oh look, it's my PCB Design tutorial! Of course I'd prefer people download it from here instead:

Dave.

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PCB design is a bit of a black art. The rules are: Keep tracks as fat as possible. Keep tracks as short as possible. Round off corners, dont have 90 degree corners. Try to keep nets as short as possible.

My software does this automatically !

instead:

Anything's black art if you don't understand it.

Unless impedance matters.

Not bad, in general.

There's nothing wrong with 90 degree corners, below several GHz.

Motherhood and apple pie are good, too.

I don't want any software making decisions for me about stuff like this.

John

instead:

Rubbish. You obviously don't understand it enough then.

On DC and low frequency stuff, yes, for high frequency stuff where signal integrity matters, no.

Sure, but not at the expense of having crappy non-orthogonal tracks at any old angle (as shown on your PCB software) - yuck.

Nothing electrically wrong with 90 degree corners (unless you want to talk many many GHz), and only then mechanically on the finest tracks.

Worse than 90 degree corners are corners >90degrees as your software appears to generate, esp on fine tracks. Think etching...

Sure.

So it automatically generates those awful looking tracks at weird angles huh? and I see a few 90 degree ones in the screen shots too, care to explain?. And the necking looks atrocious. If that's the best example of what your software can do, I suggest you remove all automated functionality, and then someone might actually considering buying it.

Dave.

These days this is somewhat board house specific -- many board houses don't have etching problems on tight corners, at least for modest angles beyond 90 degrees.

I only mention this because I've met too many PCB "designers" who learned their art back in the '70s and at the time were told that vias in pads are never OK, angles >90 degrees are never OK, lowercase on a silkscreen is not OK (!), etc.

instead:

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Well dome Dave you caught me out ! I did that not the software !

Why not? You say "expense" as if it matters.

instead:

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Then don't give up your day job to become a board designer.

Marra, if you are serious about selling this software then can I suggest the following:

- Get a proper domain name, and make your page look more professional

- Put your pricing up there.

- Have a trial download version available.

- Fix those screen shots to show some professionally laid out boards.

Regards Dave.

instead:

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Thanks for the advice Dave.

But I dont intend selling it as a business ! I sell a few copies via ebay to get feedback on the software. Its basically to keep my hand in at programming in case i decide to go back inti it professionally. The last thing I need is to be run off my feet with business.

In the last year or so it has been a hobby. I converted it from Delphi to C# which was quite a task. But it got me into C# and .net v2.0

My latest version uses .NET v3.0.

instead:

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But I have designed hundreds of PCB's over 25 years. They clearly worked or I wouldnt have stayed in a job !

I have met numerous PCB designers and they all try to make the job out to be much harder than it is. Its called "self justification"

As an electronics engineer I found my view of PCB design to be quite different to none electronic engineer layout people. I was quiet astounded by them at times doing things like tracks to crystals running half way around a board ! They should be as short as possible and right next to the micro. We got fed up at times of having to inspect layouts and ring up the PCB guy to tell him what a crap layout he had made. It often went round and round in circles causing delays. Hence in the end we took it on ourselves instead !

There are several reasons why professional PCB designers don't do it: a) Aesthetics, it simply looks ugly and unprofessional. If you did this in a professional PCB design house you would be laughed out the door. b) It can take up valuable routing realestate when the track density gets high enough. c) It can make future editing much harder, esp in the case of dragging tracks together for minimum DRC clearance for the purposes of freeing up realestate as in b).

Those are the reasons why *all* professional PCB packages will limit you to 45/90 tracks by default, and most professional designers will never deviate from that.

Dave.