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Post by Jeff Ledger on Apr 7, 2007 12:08:22 GMT -5
There are several levels of Electronics Wizards in this forum. I, being at the lower end of the spectrum. (Wizard's Apprentice? ) I've noticed some real artwork in several projects with those who are able to create their own PCB's. Gmoon's little LED userport project for instance. Even installed into a project box! I'm curious how much pre-planning is required in designing your own PCB boards, and boxes. Would some of you experts mind sharing how you get things rolling and what pitfalls you avoid to keep the end result on track? Or are you guys like some good photographers I know and simply throw out the crap before anyone else see it? I'm finding that my own style of project design is a little more fly-by-the-sear-of-the-pants. I tend to think out the problems as I come across them. (I suspect this is a bad habit developed learning to program in BASIC) For me this is a relaxing way to spend an evening, but of course solderless breadboards lack the "professionalism" level of a commercial-looking design. Because I'm doing this stuff for me alone, I doubt I'll be motivated to change it, that is until one of my projects simply runs out of room for big chunky breadboards. (It's about to happen) You wizards of electrons and rotary hand tools.. Share some of your secrets. ;D Jeff
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Post by gmoon on Apr 7, 2007 13:06:03 GMT -5
I've noticed some real artwork in several projects with those who are able to create their own PCB's. Gmoon's little LED userport project for instance. Even installed into a project box! You're giving me credit for Madmodder's work I'll comment a little later re: making PCBs, software, etc. Quick opinion: breadboarding or wire-wrapping is fine for a one-off project--MUCH quicker. But the more complicated the board, the more likely that mistakes will happen. And if you have to redo the board, or make one for someone else--what was fun the first go-around becomes tedium.
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Post by MadModder on Apr 7, 2007 13:10:08 GMT -5
Yes. It's my user port LED thingie Have you tried Ambyr Stripboard Magic V1.0? Not the best tool for major projects, but can be a help for small ones. And it's definitely good for lazy persons ;D I mostly come up with better layouts than the program though. So I don't use it. I guess I'm one of those photographers... Regarding PCB layouts I mostly get the components placement right from the beginning in the CAD program, but sometimes I suddenly (when almost finished) see an obvius error and say *curses*, rip the routing up, move some components, and restart. I use the Orcad suite for schematics and layouts. I kind of recognize the BASIC mentality. It's faster to build a fix for a problem, than fixing the problem itself. (Hmm... Microsoft? )
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Post by Jim Brain on Apr 7, 2007 16:26:55 GMT -5
I usually go through 3 stages:
Stage 1 is the solderless breadboard. They are fast, cheap, and no harm if your project loses steam or has a fatal flaw
Stage 2 is the soldered breadboard. Prototype stage. This is good for a near HW complete design, where the firmware may still be in question, but the pins are somewhat static use. If the project is a one-off, as noted above, this is the last stage.
Stage 3 is the PCB. I do it because it's a bear tracking down issues in a soldered breadboard design, even using kynar wire, if a wire fails, etc. As well, I have no desire to hand wire even a few of the boards for others.
To me, there's little pre-planning on PCBs, since I already pre-plan breadboards (you know, look at the general layout of the chips, decining which ICs and components should be placed next to another). If you already do that, PCB design is no different. If you don't do that, simply placing components on the perfboard in the order you need them or they show up in the parts list, then you need to start learning how to do it. It makes perfboard projects easier, and it helps when you jump into PCB design.
As for the tool, EAGLE has worked well for me. It has a small learning curve, and lots of people online to discuss it with. When I was just starting out on the tool in late 2004, Jeri gave me some sage advice. I was lamenting the built-in autorouter, thinking it was a product of the free nature of the tool version, and Jeri told me never to autoroute. She said they all do a subpar job, and use too many vias. I followed that advice. If you look at the first board layouts I did, you can see a few awkward spots, so practice does make "better".
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Post by gmoon on Apr 7, 2007 18:39:11 GMT -5
I also start with a solderless breadboard--I expect that's pretty standard for us all.
Once I'm sure everything works reasonably well, it's a decision of breadboard/perfboard or PCB. If it's just a quick & simple circuit, then one of those mini radio shack perfboards with the copper around the holes is fine (great for wirewrapping, too--you can solder down the components if it's for an automotive project or something that's likely to encounter vibration.)
But if it's something complex (or something I want to be proud of), I'll make a PCB.
I think Eagle is great stuff, but there are some limitations on board size/area that can be a pain. I *think* there is a proscription on using the free version for a commercial product (not that I have plans for any.)
Kicad works fine for me, I've used in 3 or 4 projects now. It has some major limitations vs. Eagle, though:
--Fewer defined parts than Eagle --Not so well supported by PCB makers (but I make my own, anyway)
I've needed to define some parts (6-pin DIN, for instance) myself.
It has one advantage, though; the actual part is 'attached' separately after the schematic. It's very easy to change a DB9 female to a DB9 male, and the schematic doesn't change at all.
I also don't autoroute, and vias aren't a problem since my boards have been one-sided. But the autorouting seems bad on all PCB design programs, especially for single-sided boards. I might let it autoroute the board, but discard 50% of the routing. The rest is done by hand. Hand routing takes time, but there is a 'zen' to it, and it can be enjoyable.
Kicad will check the board connections for you (both the schematic & the PCB), so most errors are caught at this stage.
(Nicest thing about a PCB design program: you just wire by pin # (or pin name for ICs) for connections. If the part is defined correctly, the PCB will be correct. No more spending hours looking up pins #s, trying to figure out male/female, top/bottom, front/back etc.)
I found both Eagle and Kicad had a learning curve. Kicad seemed easier, but that's probably 'cause I learned the concepts on Eagle first...
[edit] Jim makes a great point--you can spend hours trying and failing to route a board. But move the parts around a bit, and it all falls together....
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Post by Jim Brain on Apr 7, 2007 20:08:51 GMT -5
EAGLE has a similar "Entity Rules Check (ERC)" and "Design Rules Check (DRC) buttons on the panel that will check the schematic and the PCB, respectively.
gmoon makes a great point about PCB apps, the "wire by pin#", which help immensely.
There are times when the design is complicated enough that I go straight from solderless breadboard to PCB. It mostly depends on my comfort about my skills :-)
Jim
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Post by jsaily on Apr 11, 2007 9:32:52 GMT -5
One vote for Eagle from here, too! I've used PADS PowerPCB at work for a decade but Eagle has far better libraries for the hobbyist. The price for the hobby-commercial version of Eagle also is very reasonable. Making your own component libraries can be a tedious work which takes the fun out of making PCBs :/
The autorouter of PADS is quite ok for digital boards, especially when using maximum post-routing optimization levels.
I've also made my own hobby PCBs for 15 years at home, but recently we got a semi-professional prototype line at work which is nice! I can pop down to the basement after work to make good quality PCBs with solder masks. Keeping the chemicals in good shape at home is not so easy!
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Post by kaos116 on Apr 13, 2007 0:31:52 GMT -5
I am with the consensus. Breadboarding is always first. Fast for changes and when you get ready for the laying out the board, you can get a sense of where parts can go. But, I don't use Eagle software. I use Express PCB. It quick and easy. The latest version allows you to print the boards out for the etching process. Earlier versions wouldn't let you do this.
I would say that without triple checking my tracks I am at 95% getting right the first time. I usually get power tracks and ground tracks switched somewhere. It's doesn't take long when it's powered to find that problem ;D.
If I want to mount it in a project box of a specific size I try to design the board to those dimensions. Most of the time the box is later, so the boards are probably bigger than they need to be, but I have plenty of space between components for air cooling.
Alot of the PicMicros I have been playing with lately only come in surface mount packages. This makes it very dificult to do breadboarding and PCB designing. Their 64 pin TQFP is the 1cm version. That means the pins are .5mm from center to center. Now those are fun.
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