Creating a Layout: TIPS

[Shakal]

Hey guys, wazup?

So, I'm trying to make layouts with DIY Layout Creator, but it scares me a little bit. I don't know how to start! Where to place certain components, IC goes where, GND on the borders, wire soldering places, jumper, board size Vs. number of componets, which componets to start with, etc.

Well... resuming I need tips for "Layout creating rules".

Do anyone can help me? (Other people too, I think)

Thanks!

[the_random_hero]

Here

[96ecss]

I recomend RG's book http://www.smallbearelec.com/Detail.bok?no=679. It will give you all the tips you need plus the confidence to use them.

Dave

[Shakal]

"Want to design your own printed circuit boards? Don't know where to start?"

YEAH! YEAH!

Thanks guys! I'll take a look on that book.

Obs: it's a little bit hard to search for "layout" here...

[spud]

I'm by no means an old hand at this but have one experience that I can share that may help someone out that is starting to do layouts with DIYLayout creator.  But first I'd just like to say that DIYLayout is simply great!  I really think it's a fantastic tool and Bancika should get a medal or something for developing it and providing it FREE for our use!  What a generous thing to do!

On to my experience.  My first DIY build was a ROG DD (Double Distortion) on RS IC template perf board (RS# 276-150) - obviously this was more than I could handle because it remains to this day DOA.  My real problem was that I was too caught up in making the layout as compact as possible.  I spaced everything very close in DIYLayout and when it come time to assemble and build the circuit, it was very difficult to get the parts to fit and solder them cleanly (I was and still am a novice at this).  I am convinced that had I laid out the components with more space between them, I would have had a better, cleaner and working build.      20/20 hindsight

So my big revelation in all this (excuse my long winded response):

Leave yourself space to work - you won't regret it!

This brings me to a point about DIYLayout: Component Scaling.  I think the tool needs to have 1 addition/enhancment and that is better scaling of the components.  I think that you should be able to set the size of the components somehow or choose settings (Small, Med Large, X-Large, etc).  This would allow you to better represent the actual size of the pieces and how they will appear on the board.  As it is now, I think that the components are sized too small and give you the wrong impression of how they will fit on a actual board.  To compensate I now tend to use 3 holes or more for a resistor, 4+ holes for a cap, etc.  I've even gone to measuring the pieces and translating that to the # of holes used for each.  I also leave blank areas around things to reduce the risk of solder bridges causing problems, maybe 1 or 2 holes.   I have redone the DD layout based on what I've learned and plan to rebuild it the improved layout. 

Also, WRT to how to proceed from the Schematic, it depends on the complexity of the circuit - if there is an IC I try to work around that first to ensure that I have optimized the layout as it is usually the key element in those types of circuits and do drive how you place things.  If it is transistor based, I will start at the input and work my way through the circuit to the output.  I tend to re-do layouts about 2 or 3 times (sometimes more) before I'm happy with them.  Maybe if I had a better methodology, I'd be able to nail it the first time but I always see something I think can be optimized further for either space, possible noise or other issues. 

My 2 cents - for what it's worth. 

Jim

[R.G.]

Component Scaling.  I think the tool needs to have 1 addition/enhancment and that is better scaling of the components.  I think that you should be able to set the size of the components somehow or choose settings (Small, Med Large, X-Large, etc).  This would allow you to better represent the actual size of the pieces and how they will appear on the board.  As it is now, I think that the components are sized too small and give you the wrong impression of how they will fit on a actual board.  To compensate I now tend to use 3 holes or more for a resistor, 4+ holes for a cap, etc.  I've even gone to measuring the pieces and translating that to the # of holes used for each.  I also leave blank areas around things to reduce the risk of solder bridges causing problems, maybe 1 or 2 holes.   I have redone the DD layout based on what I've learned and plan to rebuild it the improved layout.

From "PCB Layout for Musical Effects" -

You cannot do good layouts if you don't have an accurate footprints.

Also, WRT to how to proceed from the Schematic, it depends on the complexity of the circuit -

PLfME: entire section on how to split up complex circuits to go from schematic to layout.

if there is an IC I try to work around that first to ensure that I have optimized the layout as it is usually the key element in those types of circuits and do drive how you place things.

PLfME: an IC is a kind of super component that forces you to work around their pinout first.

If it is transistor based, I will start at the input and work my way through the circuit to the output.

PLfME: it's more effective to slice the circuit into manageable sub circuits than to work in a given direction.

I tend to re-do layouts about 2 or 3 times (sometimes more) before I'm happy with them.

PLfME: No layout is ever final.

Maybe if I had a better methodology, I'd be able to nail it the first time but I always see something I think can be optimized further for either space, possible noise or other issues. My 2 cents - for what it's worth. 

PLfME is my $32 worth... 

[Shakal]

Thanks guys!

spud, u mentioned a word I was looking for, "Methodology"... That's what I need, something concrete, just like (or more complex than) the "Ground on borders", or just like you both said, when there is a IC u start with it.

Well, the project I'm working on has two 14 pins-IC, it's quite complex I think. I had tried to start placing the all the Wire solder points first, then start with Input until then. Now I will start by the ICs and see what happens. 

Unfortunately I can't buy the book from here... 

Thanks again! Don't be shy to give us more tips!

[petemoore]

  Count the components that you might want on the left and right side, make that a percentages number, say 48 % + 52%, [do same for up and down or...] just plunk the IC in the middle of the board, do an abstract hookup, see where changes could be made, redo with changes.
  That's how I've never done one, used to do perf layouts all the time.
  With re-drafts you'll see improvements and have choices...it's kind of an art like chess game, think 3 moves ahead on all possible moves.
  Plenty more to it, AC and transformers can output 'schtuff' like AC hum that can be picked up by sensative input wires [say on a high gain circuit], stuff like that or something to keep LFO tick out of SP may need special treatment, and might not matteror  be 'culprits' on each individual board..