Complete newcomer to PCB layout - where do I start?

[eti]

Complete newcomer to PCB layout - where do I start?

Let me say this - the last time I was shown PCB layout, was a cursory overview at college, back in the 90s. I have never done it myself, and would greatly appreciate any help in "noob form" (not "idiot form"  ) syntax. If you could point me to a tutorial, that would be superb, since YouTube is an OCEAN of them, and I do not know which is better and which is worse.

Thanks ever so much.

Matthew.

[MarkF]

I found DipTrace to be the easiest to learn after trying Eagle and KiCad.
The free version is only limited by the number of pins and two layers.

Here is a video on an old version of DipTrace (kind of lame, but all the steps to create a PCB and schematic).
Sorry, I couldn't find a good tutorial.

Note:
You can start doing a PCB layout without a schematic if your circuit is simple enough. 
Just place the components you need onto the board.

[nctnico]

Maybe take a step back before even comitting to software. Creating a PCB is solving a 3D puzzle. The first thing to do is to get a idea on how a circuit would best fit on a PCB. What are the constraints (position of connectors, buttons, LEDs, etc)? And how would the components fit on the board the best way to minimize the connections? A good exercise is to start with a piece of paper and a schematic for very simple circuit (something with an NE555 or so to blink a LED) and (re)draw the connections in the schematic in a way the wires don't have to cross.

From there try to use a CAD program to turn the same diagram into a board. I strongly recommend to draw a schematic as well because this will allow the PCB software to verify the connections are according to the schematic. Otherwise you are on your own.

[eti]

Two very helpful replies, and much wisdom found in them, especially the latter. Thank you so much.  🙂

[rstofer]

I use the ExpressPCB.com service to make my boards and I use their software.  It has no automation whatsoever and it certainly doesn't do autoroute.  Still, I have had great success with the boards I have had them make and I didn't have to spend weeks learning to use software.

[tautech]

Like Nico says, everything begins with the schematic and all the individual component characteristics start here to be transferred onto the PCB layout. Be sure to assign the individual component footprints early in your design.

Start with breaking a design into building blocks and use Net labels for circuit ground, VCC, VDD and all supply rails of each value. You might have VDD+5 and or VDD+12 for example.
Active building blocks don't need supply rails only VDD Nets of the appropriate value so to have the SW do its thing and religiously interconnect the same Nets when you import the schematic to a PCB layout.

That's a very basic overview of how best to start however remember your building blocks when you get to the PCB layout group each blocks components together then optimize each blocks layout and orientation for best connectivity paths to adjoining blocks.
At PCB import you'll be confronted with what looks like a gawd awful ratsnest of virtual connections which initially only help to rebuild your building blocks after which you mainly overlook until you start getting the best orientation of each block.
I like to keep an eye on Gnd and any VDD for each block so to have them placed accessible to Gnd pours and supply rails but of course signal In/Out paths need be accessible too.

It's lots of fun once you get the hang of the SW and a real challenge to make PCB layouts as compact as possible yet also easy enough to rework which is much too often overlooked.
Have fun and looking forward to marking your work. 

[Psi]

It's normal for your PCB design to look like shit at the start, it just takes time to untangle the mess and make everything look tidy.  There is definitely some asthenic art in laying out PCBs.

I think out of all the tasks you spend time doing in electronics, laying out PCBs is probably the most fun. At least for me.

[eti]

Well, as a complete noob @ PCB layout, I just finished a very quick mess around board using KiCad 5.X

Kickstarter begins soon, taking orders next month 

[james_s]

When I first started out I tried every PCB CAD package I could get my hands on, ranging in price from free up through stuff that would cost many thousands of dollars to actually buy. I concluded that they are all terrible in one way or another, they're all buggy and kludgey, they all have quirks, but they all work more or less the same way and if you can learn one you can learn another. I ended up settling on KiCAD and have never regretted it, it's completely free and has no artificial limitations. The process is always something along the lines of create your schematic, create a netlist from that, import the netlist into the PCB side of things, draw the board outline, arrange the components then start routing the traces. There are lots of tutorials on youtube for all sorts of different software but if you are just starting out and intending to do this as a hobby (ie you don't want to spend thousands on something like Altium) then there are few reasons to go with anything other than KiCAD, it has the lion's share of the hobbyists.

[eti]

When I first started out I tried every PCB CAD package I could get my hands on, ranging in price from free up through stuff that would cost many thousands of dollars to actually buy. I concluded that they are all terrible in one way or another, they're all buggy and kludgey, they all have quirks, but they all work more or less the same way and if you can learn one you can learn another. I ended up settling on KiCAD and have never regretted it, it's completely free and has no artificial limitations. The process is always something along the lines of create your schematic, create a netlist from that, import the netlist into the PCB side of things, draw the board outline, arrange the components then start routing the traces. There are lots of tutorials on youtube for all sorts of different software but if you are just starting out and intending to do this as a hobby (ie you don't want to spend thousands on something like Altium) then there are few reasons to go with anything other than KiCAD, it has the lion's share of the hobbyists.

Yes it's brilliant. I gave up on "EasyEDA" - what a mess of a program.

[james_s]

They're all a mess of a program, even the high priced professional stuff. It's all crap, you just have to persevere and learn to work around the quirks.

[tautech]

From what I've seen here the most common noob mistake is component holes too large and annular rings too small.
100mil is a good size annular ring unless layout density is high however even when so you can change the pad shape to retain clearances.

[nctnico]

Yep. A 3mm pad with a 0.8mm hole works well for most through-hole components. But then again, who uses through hole nowadays? Soldering 1206 SMT components is easier because you don't have to bend and cut leads.

[Nominal Animal]

I gave up on "EasyEDA" - what a mess of a program.

I was in a somewhat similiar situation – I've done electronics courses at Uni, played a bit with breadboards, but never designed my own circuits –, when I discovered EasyEDA four years ago.  I hope you tried it in your browser, as an online tool, instead of as a standalone application: I've found the latter to be not worth the effort at all.

I found the interface intuitive, as I rarely needed to look stuff up in their guides, and have done a few schematics and boards with it.  I'm kinda thinking of updating the "Cheap USB GamePad using CH551G" to CH554G, since JLCPCB has the latter in stock; might make for a funky unique gift to my nieces and nephews.

They're all a mess of a program, even the high priced professional stuff. It's all crap, you just have to persevere and learn to work around the quirks.

Applies to all software, really.

For me, it helps a lot to try and approach the program as a puzzle: How did the original developers use this tool?  How did they intend it to be used?
It may not be the optimal way, but it kinda-sorta explains why the quirks exist, and definitely helps anticipate the quirkiness, and overcome them.

You know, like when you occasionally hear a dog barking, knowing the dog by name and occasionally petting them, somehow tends to make the noise less annoying.

[PlainName]

I would also suggest EasyEDA because the grunt boring work is done for you and all you need to do is plonk things down and join them up. Think of it as the Arduino of PCBs, that let you get a taste so you know what you want in the product you'll end up with.

All of them will seem to be rubbish in some way, just like trying to build software by typing weird shit into the command line is a pain when you don't know what compilers and linkers and build tools are meant to do or when. Once you're over that little hurdle, the stupid rubbish on that first tool you used might start to make sense.

From EasyEDA the normal destination would seem to be Kicad now. You might be tempted to make that jump at the start, but I think it has a few too many interface issues that would get in the way of using it for learning PCB stuff.

[eti]

I would also suggest EasyEDA because the grunt boring work is done for you and all you need to do is plonk things down and join them up. Think of it as the Arduino of PCBs, that let you get a taste so you know what you want in the product you'll end up with.

All of them will seem to be rubbish in some way, just like trying to build software by typing weird shit into the command line is a pain when you don't know what compilers and linkers and build tools are meant to do or when. Once you're over that little hurdle, the stupid rubbish on that first tool you used might start to make sense.

From EasyEDA the normal destination would seem to be Kicad now. You might be tempted to make that jump at the start, but I think it has a few too many interface issues that would get in the way of using it for learning PCB stuff.

You're very kind to make the suggestion, but I have now decided upon KiCad, for a few reasons:

~ I like VERY find, granular control over my processes and methods, in software. I Like doing the "grunt, boring work" myself - call me a control freak, sometimes - I want not to have someone else have their code decide for me.

~ I dislike web UI interfaces - I do not feel I am in control when a web UI can suddenly change, go offline or be "improved" arbitrarily by some "update"

~ I had to jump through hoops with EasyEDA - it was my first ever use of it, and I found a large amount of friction - the UI lagged, the whole "cloud" login thing, asking me to verify, type in my Google ID every time... NO thanks - there may well be solutions around this, but mine was to follow my instincts - and I LOVE KiCad.

Thanks for all the help, and also to everyone above - I need to parse all this carefully and methodically.

PS: This video is exceptionally well explained - he crammed in VERY clear beginner instructions into a mere 5 mins and 40s!

[Refrigerator]

I started making my PCB's at the age of 14 or 13 (IIRC) with some pirated russian PCB design software.
Back then i would get an amp IC like a TDA2050 and design a board from the application schematic or a schematic found online.
Now i use KiCAD and i like it. I've tried Altium in my university but i didn't like it because importing custom components felt overly clunky and a PITA in general.
In KiCAD it's almost as easy as drag and drop.

I've noticed that there's very little to learn when designing a PCB as a hobbyist. You only need to know a few design rules and look out for a handful of gotchas that are all easy and quick to learn.
You'll be spending much more time learning to use the CAD software than learning how to design a board. Many hobbyists these days just dump components and autoroute.
When designing a PCB it's just like putting together a puzzle. You just put the pieces together in a way that makes tracks short and flow without crossing over other tracks or taking unnecessary turns.

Also when designing a two layer board think in two layers. In university we had our project presentations and i saw one guy design a PCB for his project like it was two separate one sided boards stuck back to back. The guy was completely not taking advantage of the two layer board. Seeing his clock trace zigzag across the entire board almost made me pull my hair out.

Also did you know there is a render option? The cube icon right under "Preferences" will raytrace your board, which i think is pretty cool.

[eti]

I am learning this KiCAD, and I cannot get the trace to join from my SMD transistor to the SMD resistor pad. It originates from the transistor fine, but won't stick to the res. Any ideas? TIA.

[tautech]

Generally a Net problem with component pads assigned to different/wrong Nets.

In the image above it could also be a Clearance rule issue too with the trace too close to both pads.

[nigelwright7557]

Buying pcbcad software is just the beginning whether its free or paid for.

Depending on the circuit pcb layout can be critical or not.
Its worth looking up terms like ground loops.

I designed a pcb for a USB audio mixer. Just laid it out as it came.
PCB came back , I built it up and tested it.
1 VAC of hum on output with inputs shorted.
Clearly something serious had gone wrong.
Schematic looked fine and no DRC errors in the software.

When I dug into it the charging impulses into the smoothing caps were modulating the ground line and that was being amplified by the op amps.
SO back to the drawing board and design a new pcb.
I brought in recitified AAC and into the smoothing caps on then on to the circuit.
I took all the op amp grounds to the zero volt pin from the transformer.
This time negligible hum.

Anyone can throw a pcb together, not every one does it right.

With audio stuff star grounding works for me.
Keep high and low power grounds apart except for one point at the pcb input for zero volts.

[eti]

Generally a Net problem with component pads assigned to different/wrong Nets.

In the image above it could also be a Clearance rule issue too with the trace too close to both pads.

Thanks! It won't let me specify traces < 0.2mm... is that why?

[nctnico]

Generally a Net problem with component pads assigned to different/wrong Nets.

In the image above it could also be a Clearance rule issue too with the trace too close to both pads.

Thanks! It won't let me specify traces < 0.2mm... is that why?

No, it definitely is a problem in your schematic.

For trace widths: You have to setup minimum clearances and trace widths to match the abilities of the PCB manufacturer. But leave those untouched for now; 0.2mm width & clearance is producable by any PCB manufacturer. It is better not to push the limits anyway. When I create a PCB I usually do this for a .15mm width / 0.15mm clearance manufacturing process but the traces I use are often 0.25mm.

[eti]

Generally a Net problem with component pads assigned to different/wrong Nets.

In the image above it could also be a Clearance rule issue too with the trace too close to both pads.

Thanks! It won't let me specify traces < 0.2mm... is that why?

No, it definitely is a problem in your schematic.

For trace widths: You have to setup minimum clearances and trace widths to match the abilities of the PCB manufacturer. But leave those untouched for now; 0.2mm width & clearance is producable by any PCB manufacturer. It is better not to push the limits anyway. When I create a PCB I usually do this for a .15mm width / 0.15mm clearance manufacturing process but the traces I use are often 0.25mm.

I think I have worked it out now, and it's pretty obvious when I consider it. Connecting pads between components which are not connected on the schematic, ergo the nets are not connected, won't work, else that would be changing the circuit, wouldn't it...

After having sussed this out myself, I saw confirmation of it here, not that it was needed tbh: https://forum.kicad.info/t/how-to-connect-pin-on-pcb-that-was-not-connected-on-the-schematic/23812/4

[tautech]

Generally a Net problem with component pads assigned to different/wrong Nets.

In the image above it could also be a Clearance rule issue too with the trace too close to both pads.

Thanks! It won't let me specify traces < 0.2mm... is that why?

No, it definitely is a problem in your schematic.

For trace widths: You have to setup minimum clearances and trace widths to match the abilities of the PCB manufacturer. But leave those untouched for now; 0.2mm width & clearance is producable by any PCB manufacturer. It is better not to push the limits anyway. When I create a PCB I usually do this for a .15mm width / 0.15mm clearance manufacturing process but the traces I use are often 0.25mm.

I think I have worked it out now, and it's pretty obvious when I consider it. Connecting pads between components which are not connected on the schematic, ergo the nets are not connected, won't work, else that would be changing the circuit, wouldn't it...

After having sussed this out myself, I saw confirmation of it here, not that it was needed tbh: https://forum.kicad.info/t/how-to-connect-pin-on-pcb-that-was-not-connected-on-the-schematic/23812/4

Yep, exactly.
While the ratsnest on the PCB looks like it makes no sense it's the important Net connections to help you with the PCB layout. The trick is to look past the ratsnest and visualize traces instead and where they might be run even though the ratsnest connections are all in straight lines.
Once you think you have the layout somewhat sorted use Autoroute to show the the bits that won't work then unroute and improve the layout. Rinse and repeat a few times and it all comes together bit by bit.
After a few layouts you will use Autoroute less and less as experience and the skill of trace visualization grows.

It's all real fun, enjoy the process. 

[MIS42N]

I began my PCB design learning in February, using KiCad. No idea what I was doing for a while, I thought when looking at the bottom layer I was looking from the bottom. Consequently the first one sided board didn't work out too well (but did work). Second board I designed some pads and 2 layers. Better, but forgot to clean up the screen printing and I left out some text. But it also works. Many problems I had are answered by the documentation. Some by the Internet. And some I still haven't worked out. Third board will be better again. I have no regrets about KiCad, it gets more sensible the more I learn. I just made a simple opto coupler circuit, it isn't a PCB but I dumped the circuit into KiCad, shuffled the bits until I liked the layout, then wired it up on a proto board. There's a lot to learn, but as I go it seems easier to grasp that next concept. My message is don't expect to make the perfect board first time up. It will come. People who learn a musical instrument say the first 10,000 hours are the hardest. You'll get good way quicker than that.