PCB Design - Is it OK to use "jumpers" for single sided design

Discussion in 'General Electronics Chat' started by spinnaker, Feb 14, 2010.

  1. spinnaker

    Thread Starter AAC Fanatic!

    Oct 29, 2009
    I am a newbie to PCB design. Since I am a newbie, I went with single sided to make things easier.

    I was able to design the PCB for my power supply fairly easily. I am guessing because I had components with a low pin count.

    Now I am designing the DMM portion. I am a number of components with a higher pin count.

    I am struggling to route everything without traces crossing one another. In some instances I have been able to pass a trace under a component.

    I was wondering if it was permissible to use "jumpers" (or what ever they are called) to bridge traces, using the top side of the board.

    I am guessing if they are used, they should be used sparingly?
  2. BMorse

    AAC Fanatic!

    Sep 26, 2009
    You can use jumpers if you want, I do all the time when making double sided PCB's at home.... here is a PCB I recently just made with some jumpers on top, I used the leads that are cut off of resistors and the diodes that I used in the circuit for the jumpers...

  3. t06afre

    AAC Fanatic!

    May 11, 2009
    Of course you can use jumpers. I often use jumpers to get rid of a routing problem in my hobby projects. And components like resistors make excellent jumpers.
  4. Duane P Wetick

    Senior Member

    Apr 23, 2009
    I've used insulated or un-insulated jumpers on single sided pcb's to economize costs. You can even buy 0 ohm resistors if you don't want to use wire. For feed-thru terminal blocks, its best to use plated-thru holes and double side pads because screw torques sometimes want to lift solder pads.

    Cheers, DPW [ Everything has limitations...and I hate limitations.]
  5. SgtWookie


    Jul 17, 2007
    Sure, you can use jumpers.

    It's best if you can minimize their use, because otherwise you will have more holes to drill, more wires to solder/trim, and more points that could cause you problems.

    Try to place jumpers in just one rotation; either 0° (Y-axis) or 90° (X-axis). If you start using jumpers in both rotations, you'll likely find yourself "boxed in" in a hurry.
  6. dsp_redux

    Active Member

    Apr 11, 2009
    Like t06afre mentionned, try to use resistors or components from your circuit as jumpers. Make sure you don't short the traces with the component tough.
  7. retched

    AAC Fanatic!

    Dec 5, 2009
    0 ohm resistors are used as jumpers often in surface mount board work. You can feel free to jump all you want. It can become a problem in higher frequency applications. All the jumpers can work as extra antennae leading to unwanted noise in your project.
  8. spinnaker

    Thread Starter AAC Fanatic!

    Oct 29, 2009

    Thanks for all of the quick and great responses. I am glad to see even the pros use this practice and on double sided boards too.

    Yes I know I can use components as jumpers. I did this a lot on the power supply version of my project.

    I figured added jumpers were kind of the "goto statement" of the PCB world. :) Try not to use them, but if you do minimize them. From the sounds of it though, it is almost not as bad as using a goto. :)

    Is it also acceptable to make kind of a hybrid PCB / (sort of) perf board? Using wire wrap wire to make connections from pin to pin? Yes I know minimize them. But is some acceptable?

    If so, (for a newbie) is this preferable over narrower traces and trying to weave trace in between pins?

    I know I have seen wire wrap on professionally designed boards before but I am pretty sure that was after the fact, for either fixing a mistake or upgrading the design without having to toss out the whole board.
  9. k7elp60

    AAC Fanatic!

    Nov 4, 2008
    I use the prefabricated colored jumpers that are used on proto boards for jumpers. The colors specify the length in 0.1"s of inches.
  10. spinnaker

    Thread Starter AAC Fanatic!

    Oct 29, 2009
    So you are saying that you use point to point wiring on a PCB or you use the prefab colored jumpers just as jumpers?
  11. SgtWookie


    Jul 17, 2007
    Try to avoid making your board look like a hybrid spaghetti. ;)

    Don't forget that since you're using a uC, you have lots of options to swap I/O pins around. Frequently, that just involves changing a few lines of programming or port mapping. Just start off with routing those that can't be reassigned, like the Vcc/Vdd, Vss/GND, and your MCLR pin (if you're using it with an in-circuit programming/debugging connector; not a bad idea to do so with such prototypes).

    You may have several I/O pins to choose from for the ADC or comparator inputs.
    Then routing the other I/O lines comes last.
  12. spinnaker

    Thread Starter AAC Fanatic!

    Oct 29, 2009

    Yep already made some changes of pins! :)

    And I think I can make a couple of more.

    I might get it down to where I only have one or two point to point wirings and 2-3 jumpers.

    I can really see where, you may need to go back to the orginal design and change that. Then maybe breadboard it, then go back to your PCB.

    Though I guess more experience, helps in the original design.

    ExpresspCB should really think of turning this into a video game. They would make a fortune. :)