Building on perfboard, best way to run Vcc/GND rails?

Discussion in 'General Electronics Chat' started by lowprofile, Nov 26, 2011.

  1. lowprofile

    Thread Starter Member

    Oct 31, 2011
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    Ok, I feel a bit silly asking, as if the answer might be very obvious, but the stupidest questions are ones that aren't asked, so here goes :)

    I'm building a project on perfboard. There are a lot of ground connections. Should I allocate an area of the board next to where the battery connects and route all ground connections directly there? Or is it better to chain them together (such as: ground of IC1 connects to ground of IC2 connects to ground of IC3 and then to the ground wire of the battery)?

    I understand that from a node point of view they are the same, but I am not certain which is the best practice from a practical standpoint. I am concerned with neatness, reliability (less flying wires?), and any effect either approach might have on audio-frequency signals.

    I welcome any wisdom you can offer on perfboard layouts and power rails :)

    Thanks!
     
  2. Wendy

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  3. lowprofile

    Thread Starter Member

    Oct 31, 2011
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    I mean the stuff that's one pad per hole, specifically. Thanks for the examples!
     
  4. Wendy

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  5. EarlAnderson

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    Nov 13, 2011
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    The best setup for your voltage rails on perfboard, is around the perimeter. i usually leave a gap 1 pad wide between both rails to prevent accidental shorting
     
  6. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    I know people will have their own preferences, but "one pad per hole" board is much slower to work with than veroboard (0.1" stripboard).

    With veroboard you can use some strips as power and ground busses, not to mention things like signal busses. You can cut tracks in a few seconds (I use a cordless screwdriver with a 1/8" drill bit to cut tracks) so you can build a finished circuit in a fraction fo the time perfboard takes and much less soldering and much neater! :)
     
  7. MrChips

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    Oct 2, 2009
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    Wiring point-to-point power and ground is not a good idea.

    If you insist on using perfboard (one pad per hole) I would run bare wire on the solder side along the length of the board to create power and ground bus rails. Run the wire towards the edge of the solder pad so that you do not block the holes. Now you can connect to the bus rails. (I don't have a photo immediately to make it clear.)

    I agree with RB and I use veroboard. It is a lot easier. I use an Exacto knife to cut the copper at the holes. Sometimes I save the hole by actually cutting the copper bridging the next hole. This gives a more compact circuit.
     
  8. Wendy

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    I have quantity in several varieties, my favorite is this actually...

    [​IMG]

    I use a lot of single pad material though. Nowdays I draw it, the drawing is slow, but making it speeds up, looks neater, and fewer mistakes. In general I find it has much better high frequency characteristics, though the dead bug and Manhattan styles are much better for RF.

    The strip board had just become available in my area. I'm transitioning to PCB nowdays.
     
  9. Yako

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    Nov 24, 2011
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  10. Yako

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    Nov 24, 2011
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    I find this type of board too hard to work with. Too restricted. But I use wire wrap, and my projects are usually very complex.
     
  11. Wendy

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    Alcatel had whole sheets of the stuff, 8"X11", that we used to build test fixtures. I suspect the complexity was above what your are used to, 30 IC projects were common. I was a test tech with some metrology experience at the time, but some of the operators were artists. They didn't know electronics for squat, but they could build some of the prettiest stuff I've ever seen, then the engineers would get ahold of it, and "fix" it. It usually wasn't so pretty after that.

    True wire wrap was dropped by industry during the 90's due to reliability problems. It is a wonderful technique, easy to use, but the wires develop intermittents that are a stone bear to find after 5 or more years of service.

    For home use I tend to 5 chips max.
     
  12. Yako

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    Nov 24, 2011
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    It is project dependant really.

    For audio, one cannot have ground loops, so a technique called 'star-point earthing' -- is used.

    In many cases, a ground plane can be bridge-soldered on the outside of the board. I often create a system that is based on demand, whereas I just series connect ground points to a common location.
     
  13. Yako

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    Nov 24, 2011
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    And the rest.

    You're talking digital electronics right?
     
  14. Wendy

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    Combination usually. Before it was Alcatel it was Rockwell International, Collins Radio Division. I worked for both, as I was part of the property that was sold. I was a lead tech for 15 years, then went into machine maintenance. I got to do a lot of prototyping over the years, but more into the repair of old stuff other people came up with. Collins Radio, before Rockwell bought them, was heavy into radios of all types (but of course). One of the odd side effects on the company culture is every product was a "radio" whether is was or not.

    Bringing it back on topic, something I have found is if you lay a project on single pad format, and draw it like I do, it becomes a dream to translate to a printed circuit board (PCB). The thought processes are very similar.
     
  15. Yako

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    Back in the 90's I used to work with some guys that developed hardware and software for a quater of a million-dollar (at the time) -- drum scanner as used in the now defunct pre-press industry.

    They (not me) -- prototyped boards with hundreds of DIP ICs. Mostly buffers.
     
  16. Yako

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    Nov 24, 2011
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    Is it? I struggle with it no matter what way I go.

    I am talking single-sided PCBs here, which give you a choice of either:

    • a. Spend more time and think
    • b. Use a wire link ...
     
  17. tracecom

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    Apr 16, 2010
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    Some of my prototypes are ugly on the bottom, especially when I try to make them look good on the top. This one worked the first time I put power on it, and is still working.

    To the OP, the black wires and everything connected to them is at ground. The red wires and the pink wires are regulated voltage. I don't bother insulating the wires that aren't in danger of shorting to something.
     
  18. lowprofile

    Thread Starter Member

    Oct 31, 2011
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  19. MrChips

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  20. THE_RB

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    Please don't be offended Tracecom (as my criticism is of the perfboard, not of your workmanship) but that messy wiring on the bottom of the board is the exact reason why I think perfboard is much inferior to veroboard and would advise beginners away from using it.

    Here's a board I did that was thrown together VERY quickly, with no effort spent on appearance. But you can see the ease of wiring and of tracing signals, and putting probes on the board etc.

    [​IMG]

    Pre-tinned veroboard (don't get the copper colour stuff) is a really good way for beginners to whip up projects.
     
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