Removing breadboards: Suggestions for alternative power rails? - Page 1
Forum section: electronics / beginners

author: Jay112
author_rank: Regular Contributor
timestamp: May 13, 2016, 08:43:25 pm
content: Based on some advice on this forum, I decided to convert most of my breadboard stuff to PCBs. So far most of it is going smoothly.After I removed some components/sensors from some breadboards, I realized that most of the remaining wires connected to the breadboards are just for power and ground. I'm wondering if you have some suggestions for what to do with all those power/ground connections. Is there an easier way than just soldering them all onto a PCB? I guess I could just leave them on the breadboards, but it's very unproductive to have to keep checking them for loose connections every time I have a problem.As a sidenote: It looks like I'm dealing with about 30 connections to power and ground, so about 60 connections total.

author: Cubdriver
author_rank: Unknown
timestamp: May 13, 2016, 10:13:53 pm
content: Jay, I'm afraid I'm not quite sure what you're asking here. Are you making up printed circuit boards for your circuits, or are you transferring them from solderless breadboards to the PC boards that have the same pattern as the solderless breadboards, but that are soldered rather than making the connection with hidden terminal clips that the leads press in to on the original breadboard?I'd expect that if you were putting the circuits onto custom boards that the power and ground connections would be part of the circuitry on the board, thus making the additional jumpers mostly unnecessary. If you're doing the breadboard-style PCBs, you'll still need to make the connections to the power and ground rails.-Pat

author: Jay112
author_rank: Regular Contributor
timestamp: May 13, 2016, 10:33:06 pm
content: Quote from: Cubdriver on May 13, 2016, 10:13:53 pmThanks for replying. I apologize my writing wasn't very clear.Yes, I'm just transferring my circuits from solderless breadboards to a custom bread-board style pcb.I moved the more sensitive sensors from the solderless breadboards to the pcb. Some of the sensors are: temperature, gas, humidity, barometer, etc. When a sensor was moved from the breadboard to the pcb, its power and ground connections were also moved to the pcb.But even after removing the sensors, I still ended up with lots of power/ground connections. It would take me a while to trace where they're all going, but I'm guessing most of them are for less-sensitive things, like tact buttons.Is it best to just solder all of those power/ground connections to a pcb? Or is there any kind of easier way to do it?Thanks!

author: Cubdriver
author_rank: Unknown
timestamp: May 13, 2016, 11:06:10 pm
content: Any possibility of posting a photo of one of them?

author: Jay112
author_rank: Regular Contributor
timestamp: May 13, 2016, 11:30:31 pm
content: Quote from: Cubdriver on May 13, 2016, 11:06:10 pmThese are 3 pictures I just took. I'm in the middle of a lot of restructuring/reorganizing, so things aren't the way I want them to be yet, and I have lots of loose / disconnected connections all over the place. Also I just started with electronics about a year ago, so I'm still learning the basics.The following 2 pics are PCBs I just soldered today:And this is one of the solderless breadboards that's remaining. I was planning on moving the last 3 components (buzzer, mosfet, and digital pot) to a PCB, and then that large breadboard will be just power/ground connections (which I'm planning on moving to a different system, possibly soldering them all to a PCB). I have another solderless breadboard that I removed components from, and the entire bread is now just power/ground connections.

author: Jay112
author_rank: Regular Contributor
timestamp: May 13, 2016, 11:33:50 pm
content: Also I should add that I'm not adding features to the system very much recently, and most of the wires that are there have been there for months. It's probably okay if the wires are connected permanently now.

author: Cubdriver
author_rank: Unknown
timestamp: May 13, 2016, 11:45:48 pm
content: Ahh, ok, that clarifies things a lot. I gather many of the flying leads on the original solderless breadboard go off to the external switches and whatnot you mentioned earlier.For what it's worth, as big of a PITA as it will be, I'd ultimately trace them out and get everything onto the soldered board. Otherwise you're apt to be tearing your hair out trying to trace things that don't work that wind up being loose connections to the power or ground busses on the solderless board.And also for what it's worth, I generally put the components on the side opposite the copper traces, with the leads sticking through the board, and solder them on the copper side. That way the components themselves can't accidently short the bare copper traces to one another, and you have a clearer area to solder in - just the lead poking through the board, instead of having to solder around the component as well. Just something to consider for the next one.-Pat

author: Jay112
author_rank: Regular Contributor
timestamp: May 13, 2016, 11:51:57 pm
content: Quote from: Cubdriver on May 13, 2016, 11:45:48 pmThanks for all the help, Pat! I appreciate it!Those were my first stripboards, and I had no idea how to solder them, so I'm glad you made the suggestion. My biggest question was whether to have the wires on the front or back, and I tried different ways on each board. But I totally wasn't thinking about which side the components should be on!Yeah, it's probably better to just eventually solder all the power/ground connections, and I'll probably end up doing that in the near future. It's super annoying to troubleshoot a loose connection.Thanks!

author: Cubdriver
author_rank: Unknown
timestamp: May 14, 2016, 02:16:24 am
content: My pleasure!-Pat

author: Ian.M
author_rank: Super Contributor
timestamp: May 14, 2016, 07:13:20 am
content: Sounds like you need a power distribution board.Take a piece of Veroboard, populate with 0.1" pitch headers with enough ways for all the power rails you use, and put mating shell and female crimp contacts on the end of all the sensor cables etc. For ground, and higher current power rails, use two adjacent tracks on the Veroboard and bridge them at intervalsCrimped contacts also solves the reliability problem of soldering stranded wire to PCBs - Solder wicks up the wire and causes a hard spot, so unless you strain-relieve it so it doesn't get bent near the hard spot, if the wire flexes often enough, the strands start snapping at the end of where the solder wicked to.All wires should connect top side. This can be problematic for big wires, requiring drilling out holes to the wire diameter, but if you connect them track side and they ever get yanked, it can rip the whole track right off the board.

author: Jay112
author_rank: Regular Contributor
timestamp: May 14, 2016, 02:02:18 pm
content: Quote from: Ian.M on May 14, 2016, 07:13:20 amThanks for the info!I've never heard of this method. Might you be able to post a picture of how it's supposed to look?I've never heard of Veroboard either, but an ebay search showed the following, which looks like it should be very handy for power distribution:The only strange thing to me is that it says "Copper free". Is that normal?http://www.ebay.com/itm/5-x-Prototyping-PCB-Circuit-Board-Stripboard-Veroboard-94x53mm-Copper-Free-Ship-/281765908639And is this the type of pitch header you were referring to? (I happen to have a bunch of these, but just wanted to confirm it was the correct ones):Also I've never heard of crimp contacts before. Are either of the following by chance the correct ones?http://www.ebay.com/itm/D-Sub-Crimp-Contact-Pin-Female-50pcs-per-lot-/351732178286http://www.ebay.com/itm/Baomain-1000Pcs-Wire-Copper-Crimp-Connector-Insulated-Pin-Terminal-for-AWG-18/181588009105Sorry for all the questions. Thanks for the help!

author: Ian.M
author_rank: Super Contributor
timestamp: May 14, 2016, 02:19:38 pm
content: "5 x Prototyping PCB Circuit Board Stripboard Veroboard 94x53mm Copper.Free Ship"Does that help? It certainly makes more sense than "Copper Free.Ship"!If you need to cut tracks, you'll also need a Vero stripboard track cutter or a brand new 4mm drill bit epoxied into a piece of dowel so you can twiddle it between your fingers.No. Those aren't the right headers (unless stated otherwise the assumption is that a header has male pins) or contacts/pins for them.Start here:https://www.pololu.com/category/71/wires-with-pre-crimped-terminalsWatch the video!

author: Jay112
author_rank: Regular Contributor
timestamp: May 14, 2016, 02:54:57 pm
content: Quote from: Ian.M on May 14, 2016, 02:19:38 pmYes, "Free Ship" makes way more sense!Thanks for the link! I just watched the video.I went back and re-read your posts, and I think I understand it now. Basically the Veroboard will have lots of male headers coming out of it, and I'll have female crimped connectors on the ends of all my wires I want connected there, right?I understand why high-current rails might require using 2 adjacent tracks connected, but could you please explain to me why it's good to double up the ground rails too? I got the impression from your first post that the ground rails should be doubled up by default.

author: Ian.M
author_rank: Super Contributor
timestamp: May 14, 2016, 03:07:31 pm
content: Yes, lots of male headers, each strip oriented at right angles to the veroboard track direction, a bit like a fakir's bed of nails. You'll use contact shells to group the female contacts on the wire ends so each sensor simply plugs onto one strip of male headers without a lot of fiddly individual wires to hook up. If you get the track cutter you can use the veroboard as a backplane for all the interconnects including signal/data - simply fit the header strips at 0.4" spacing which gives you room for two connections + one track cut between them so you can patch signals wherever they need to go with soldered in jumpers.I'd double up the grounds or solder a stout solid copper bare wire along the ground track for signal integrity - if your ground voltage is bouncing around, your analog levels will be all over the place and if it gets too bad it can even corrupt digital signals, so its *ALWAYS* a good idea to minimise the ground resistance.