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Topic: From breadboard to perfboard (Read 2061 times) previous topic - next topic

Ischia

Hi,

I need to build a set of 8 pushbuttons with built-in LEDs. After messing around with breadboards I'd like to make something more permanent. After laying out the base components on a perfboard and drawing some lines in Photoshop, I got a bit overwhelmed by the potential mess of wires (cf. photo).

Admittedly very simple, this is my first "serious" circuit. But the number of wires dangling from the back promises to be quite large... I'd appreciate some advice from those who've already built some: how to avoid a total mess behind the perfboard, how to optimize layout etc. Maybe there are some "helper" components I should know about?

Thanks a lot.


marco_c

Think about running the horizontal and vertical parts of the paths on two different sides of the board.
Arduino libraries http://arduinocode.codeplex.com
Parola for Arduino http://parola.codeplex.com

Jack Christensen

Things can get to looking messy but still be OK from an electrical standpoint. Here are a couple recent threads along similar lines. BTW, interesting buttons, where did you get them?

http://arduino.cc/forum/index.php/topic,110347.0.html
http://arduino.cc/forum/index.php/topic,110462.0.html
MCP79411/12 RTC ... "One Million Ohms" ATtiny kit ... available at http://www.tindie.com/stores/JChristensen/

Ischia

#3
Jun 21, 2012, 02:13 pm Last Edit: Jun 21, 2012, 02:25 pm by Ischia Reason: 1
It's funny, I showed a button like that to a guy in an electronics shop, and he said, "Great looking buttons, where did you get them?"...

Actually they were 20 for two euros at an electronics shop counter in Paris (France). While looking for specs I did a Google Image search for "LED pushbutton" and found a site with something similar here. The ones I have look a lot like the one on the bottom right, except the LED is red and not orange.

Small issue: they're not really perfboard or breadboard friendly -- as the LED contacts are off-center you have to twist them slightly to make them fit (cf. photo). I really don't know who's responsible for this...

Can't be more specific I'm afraid.

Erni

Sparfun has some that looks the same

http://www.sparkfun.com/products/10442

xolroc

20 for €2?  That's insanely cheap!  You have no idea how lucky you were to find them at that price; the only similar thing I can find is €1.54 each!

Ischia

I know, I wanted somewhat bigger LED-buttons but they starting at 4€ apiece... so I settled with those, which are really small BTW (i.e. not really ideal for prolonged use with adult fingers).

Nick Gammon

I got one of these the other day. That's bigger ...


Please post technical questions on the forum, not by personal message. Thanks!

More info:
http://www.gammon.com.au/electronics

Docedison

Cheap parts of all kinds can be found at Electrodragon, I was Blown away at some of the prices.... locking PB switches for $0.05 -$0.10 Ea... I just spent about $50.00 there, went nuts. Check This out
http://www.electrodragon.com/?product=3-2-tft-lcd-arduino-adapter-shield

Doc
--> WA7EMS <--
"The solution of every problem is another problem." -Johann Wolfgang von Goethe
I do answer technical questions PM'd to me with whatever is in my clipboard

Docedison

Getting back to the original thread topic... Neat Switches BTW and a Nice looking place to shop, especially if one was thinking about opening up a little shop... The real issue with your layout is that it 'looks?' like you literally wired it pictorially instead of pictorially wiring it literally. The "literal" method is to place the parts as close together as use and wiring limitations apply. Obviously one wouldn't wire pushbuttons any closer than a keyboard or IC's and other parts any closer than wiring complexity and size limitations dictate but there is in your layout, as neat as it is... a great deal of 'air', wires that longer than strictly needed and the IC a lot farther away than easy wiring would permit. I do admire the switches but think that I would have wired it a little tighter together as it does complicate replication. IMO

Doc
--> WA7EMS <--
"The solution of every problem is another problem." -Johann Wolfgang von Goethe
I do answer technical questions PM'd to me with whatever is in my clipboard

Ischia

@Doc: thank you for the suggestions. Like I said, first "serious" circuit, and it will be even more complex when I'm done with it (another HC165 in cascade with 8 more switches in a 2x4 arrangement). There is "air" between the switches because, like I wrote above, they are quite small and to keep the entire thing useable I need to account for real fingers.

I'm still confused about one aspect of the actual soldering process. In the Make: Perfboard Prototyping video, on the bottom side of the perfboard connections are made using solder only. Wires, on the other hand, are used on the top side. I was thinking of running wires at the bottom side because I have 3 16-leg ICs and I can't possibly smear my entire perfboard with solder and make it out alive.

So, any "best practices" out there (apart from the layout itself, which I'll optimize further of course)?

Grumpy_Mike

I use the top for the wires and the bottom just for the tracks. Try and make the top wires horizontal or vertical. That way you can use tinned copper wire with no insulation and it looks neat. Use the copper tracks on the underside to bring the connections to a point where these links can be made. You won't be able to do all the connections like this but it should minimise the "mess".

Ischia

This perfboard doesn't have copper tracks on the underside, I only have copper circles around each hole. Are you suggesting that I create "tracks" with solder?

Ischia

Since I'm somewhat overwhelmed by this, I've drafted a quick preview in OmniGraffle (cf. attached screencap) which makes it easy to rearrange stuff. In no way can I imagine a solution suggested by @marco_c, i.e. separating the vertical and horizontal paths. Whatever I do, from a topological point of view the wires will always be crossing, and I haven't even started to draw the wiring of the second half (on the right) -- which is arranged differently but still a disaster waiting to happen.

Should I keep the wires "floating" on the backside, like a small jungle?

compuslave

I have wondered many times how in the hell people can design complicated layouts. I am a Linux user, and have used the gEda package before. Anyone have any tips on using the layout tool in gEda? Will it actually help you decide the best layout, or is it just a glorified autocad for circuits? I have never even tried it since I have only taken one project from the breadboard to pcb and I just jumpered all the connections because I could not wait to have a working unit. Next time I'd like to do it right.
Never judge a man until you walk a mile in his shoes. But, by that time you're a mile away and you got his shoes, so screw em'

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