How do you plan out a circuit on perfboard?

Discussion in 'General Electronics Chat' started by torea, Jul 24, 2012.

  1. torea

    Thread Starter New Member

    Jul 3, 2012
    16
    0
    Hey all, hopefully this is in the right place.

    I made two different microphones this weekend, and did it from scratch with just a schematic (no prototypes or other models to look at). I did them both on perfboard, easy enough. But it made me think: Is there a better way to lay this out?

    So, do you have any special processes or procedures to make sure your circuit is laid out in an efficient, functional, and (when needed) small-as-possible way?

    I usually just make a list of the points where components meet, and use that to help me lay stuff down. I also try to lay it out similar to the way the schematic does when possible, since that helps me remember what goes where.


    Thoughts?
     
  2. #12

    Expert

    Nov 30, 2010
    16,252
    6,751
    I use a piece of .1 square graph paper and a pencil. Better to wear out the eraser than the leads on the parts moving things over and over again.
     
  3. torea

    Thread Starter New Member

    Jul 3, 2012
    16
    0
    That's a good plan, I've done that as well. Do you just create draft after draft until you find something you like? How do you approach something where there's a lot of crisscrossing of parts (i.e. when the layout isn't straightforward).

    Thanks!
     
  4. pilko

    Active Member

    Dec 8, 2008
    213
    20
    • bb.jpg
      bb.jpg
      File size:
      83.9 KB
      Views:
      206
    • sb.jpg
      sb.jpg
      File size:
      160.8 KB
      Views:
      258
  5. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    7,386
    1,605
    I do most of my proto work using SMD parts using proto boards with just pads on 0.1" centers. 0805 parts fit nice between 2 pads. Then if you use SMD parts some adapter boards are great to get 0.1" centers to wire to.

    First I pick a nice piece of perfboard to built it on. The boards from Radio Shack are useful for short term projects such as a test board, but I do not typically use them for anything permanent. Vector makes some very nice ($$$) boards, and you can find some very good inexpensive boards off China suppliers on EBay, cheap if you get free standard shipping, takes about 2 weeks to get to me so I stock some of those in various sizes.

    I've got Autocad for mechanical layouts, and I will start by making a 1:1 layout of the perf board showing the outline, the holes and the pads. Then I draw the parts I will use and build the thing on paper. You can scoot parts are you want till you get things tight. Sorry I don't have any handy or I'd post some captures.

    You also get a great drawing to follow when your troubleshooting, or looking back on your work months/years later.
     
  6. Wendy

    Moderator

    Mar 24, 2008
    20,764
    2,535
    Personally I free hand, then draw. This series was done by me...

    The 555 Projects

    but I have done others.

    The trick to fit all the parts, then interconnect them.

    This comes to mind, for example.

    http://forum.allaboutcircuits.com/showthread.php?t=12405

    http://forum.allaboutcircuits.com/showpost.php?p=140262&postcount=39

    I also do perfboards. In some ways they are easier, the trick is to get accurate drawings of the parts.

    High Power LED Flasher

    You can download my library of templates from my blog in the form of PaintCAD, a set of templates I've made over the years. I use M/S Paint to draw with them.

    Bill's Index

    Introduction and PaintCAD

    Occasionally I update my drawings, and upload the later revision of PaintCAD.
     
  7. GetDeviceInfo

    Senior Member

    Jun 7, 2009
    1,571
    230
    I'll typically work straight off the schematic. I will use color to group functions. I'll also lay down power/return first, followed by busses, then finish up with control.
     
  8. #12

    Expert

    Nov 30, 2010
    16,252
    6,751
    First I redraw the schematic for the least number of crossovers, then look up the pinouts of the parts to find that they are not in the order I used to redraw the schematic. Eraser, eraser, change the arrangement. Draw that in the middle of the piece of paper and add on power in and output out, try to make a path to the edge of the board for sensor inputs, and indicator outputs, then snuggle the parts closer together using mostly the eraser.
     
  9. KMoffett

    AAC Fanatic!

    Dec 19, 2007
    2,574
    230
    I use ExpressPCB. I often will prototype a design on perfboard, then decide whether to go ahead and order PCBs. I do the schematic, then the linked PCB layout with all components on 0.1" centers. I've had to create some custom components for X0.1" footprints...but that's easy with ExpressPCB. I even take screen-shots of the PCB layout, then reverse the image in Photoshop, so I have a bottom view of the traces. I then replicate the traces point-to-point with stripped and unstripped Kynar wirewrap wire. Stripped for bottom traces, and unstripped for what would be top traces, but placed on the bottom of the perfboard. The link between the schematic and the PCB layout helps me reduce the chance of errors with the perfboard.

    Ken
     
Loading...