SparkFun Breadboard Power Supply Stick 5V/3.3V

This is a very simple board that takes a 6-12V input voltage and outputs a selectable 5V or 3.3V regulated voltage. All headers are 0.1" pitch for simple insertion into a breadboard.

Input power can be supplied to either the DC barrel jack or the two pin header labeled + and -. Output power is supplied to the pins labeled GND and VCC. Board has both an On/Off switch and a voltage select switch (3.3V/5V).

The two pairs of GND and VCC holes are spaced such that when connected to our Basic Breadboard both power busses will be powered.

Check out our Unregulated Power Supply Tutorial!

Note: Headers are not supplied. You will need to supply your own headers to connect this board to a breadboard. Check below for some breakaway header strips.

Note: We've released a new version of the SparkFun Breadboard Power Supply Stick, it can be found here! The new version functions the exact same way as this older model but we've made a few changes to footprints, the silkscreen, and added a second set of pins that output to the breadboard to help with stabilization. Go check it out!

  • 6-12V input voltage via barrel jack or 2-pin header
  • 3.3V or 5V regulated output voltage
  • ON/OFF switch
  • Output voltage select switch
  • Power status LED
  • PTC fuse protected power
  • 5.5x2.1mm center positive barrel jack
  • 2.15x0.65"
  • [Schematic]( Power Supply - SMD v13.pdf)
  • [Eagle Files]( Power Supply - SMD
  • GitHub (Design Files)

SparkFun Breadboard Power Supply Stick 5V/3.3V Product Help and Resources

Core Skill: Soldering

This skill defines how difficult the soldering is on a particular product. It might be a couple simple solder joints, or require special reflow tools.

1 Soldering

Skill Level: Noob - Some basic soldering is required, but it is limited to a just a few pins, basic through-hole soldering, and couple (if any) polarized components. A basic soldering iron is all you should need.
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Core Skill: Electrical Prototyping

If it requires power, you need to know how much, what all the pins do, and how to hook it up. You may need to reference datasheets, schematics, and know the ins and outs of electronics.

2 Electrical Prototyping

Skill Level: Rookie - You may be required to know a bit more about the component, such as orientation, or how to hook it up, in addition to power requirements. You will need to understand polarized components.
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Looking for answers to technical questions?

We welcome your comments and suggestions below. However, if you are looking for solutions to technical questions please see our Technical Assistance page.

  • Member #305284 / about 12 years ago / 7

    Would be nice if it had 5V for one rail AND 3.3V for the other. Also, what about same output pins at the other two corners so it sits flat on the breadboard?

    • rben13 / about 11 years ago / 2

      I second the idea of extra output pins or no connection pins on the other two corners. That would make the board a lot more stable and reduce wear on the four pins currently holding it onto the breadboard.

      • bfesser / about 11 years ago / 1

        Well, it only does plain 5 V, but I found a kit that has four sets of pins for stability (from Solarbotics):

        (If linking to other vendors is forbidden, I apologize. I don't see it as a competitive product, however.)

    • mctom987 / about 11 years ago / 1

      Totally agree on this. 5 and 3.3V is way better than 5 or 3.3V

    • M-Short / about 11 years ago / 1

      I soldered the headers to my board and then removed the plastic part of the headers, now the board sits flat on the breadboard which is nice.

    • bfesser / about 11 years ago / 1

      I like these suggestions, however it would be difficult for them to have a breadboard supply that matches everyone's wants and needs. I suggest you take their Eagle files/schematics, modify them to your liking, and put it up as a Tindie fundraiser.

  • Member #114783 / about 13 years ago / 2

    What kind of Amerage will this little board kick out?

  • Member #71730 / about 13 years ago / 2

    Oh, quit crabbing about price! SparkFun is always coming out with new fun stuff that's good quality at a good price. They always try to incorporate our suggestions in revisions to products and are always ready to explain or help.
    How many tutorials do you see on those everythings-cheep sites? Do they EVER answer e-mails? Do they use quality parts or floor sweepings?
    Go ahead and take the chance of getting burned by saving a couple of bucks. I'll stick with SFE and know I'm getting quality material. Besides, they're nice folks.

    • Hey Hey, I love sparkfun. I never said they where not any good.
      I own and the shop. I help all my customers personally. Ive even coded for many. I help out on ElectroTech Online Forums a ton.
      My Parts are about 90% mouser/digikey. So no sweepings here. I test everything myself and if support is needed my customers know i will be there.
      Dont try and bring down small companies. Just because sparkfun has been around longer and has a huge fan base does not mean they are better.
      Id like to think my prices are beyond fair. I make close to nothing... why??? to help the community GROW! the more you charge the less people can get into certain things.
      Why you think there is theft in the world? Because people who have money to spare think its cool to pay for expensive items which do the same as cheap stuff and try to pass it off as better. Hence everyone thinks its better...
      I can keep going but seeing as this is not a forum ill cut it here...

  • HungryMaggot / about 13 years ago / 2

    what output amps?

  • Member #664182 / about 9 years ago / 1

    An easy way to stabilize this board is to solder a single header pin into one of the through holes at the tail of the board (the ones labeled "+" and "-".) Soldering pins into both holes will result in a short when the power supply is plugged into your breadboard, likely damaging or destroying the power supply -- so DON'T DO THAT! Adding just that fifth pin is really enough to do the trick.

    As others have suggested, it is also possible to skip the fifth pin and remove the plastic spacers, once the headers have been soldered in, allowing the board to sit flush against the breadboard.. My only concern with this approach is that it could potentially interfere with heat dissipation.

  • stevenvh17 / about 9 years ago / 1

    If you want to use this for 5V, then 6V in isn't sufficient, you'll need 3V more than the output voltage. With this is mind the LM1117 would have been a better choice, especially if you want to limit the input voltage to 12V (for dissipation reasons).

  • jpkelly / about 9 years ago / 1

    Am I crazy or is the output polarity reversed from the standard polarity of the rails on proto boards?

  • Member #589969 / about 10 years ago / 1

    Can I power this off of a car, or is the 13.8V I get from the alternator going to fry it?

  • Member #503874 / about 10 years ago / 1

    Hi recently, one of the components was exploded was burning. May I have BOM for this part, so that I can buy some components and replace it. Thanks.

    • The Eagle files are posted above. This will tell you exactly what part you need and what values. Sorry to hear your component exploded!

  • joran / about 11 years ago / 1

    the power on this thing was very spotty ... further investigation showed that only one of the legs from the barrel jack is attached to the pads. can I just solder this connector with a normal soldering iron and solder? I dont have a SMT setup...

  • nixpulvis / about 11 years ago / 1

    I had a cool idea for a breadboard stick, what about adding some multimeter ports and a switch to add the multimeter to the circuit for easy current measuring. Not sure if it's worth selling a whole new product, but it's something I'd buy, or make myself.

  • Member #441916 / about 11 years ago / 1

    The spacing on the pins doesn't fit some breadboards, there is another type thats common with slightly wider spacing between the the power rails, for the next revision maybe put 2 sets of output pins at the different spacing and have them at opposite sides of the breadboard so it sits flat and fits more breadboards.

  • Jim36 / about 11 years ago / 1

    I have the previous version (PRT-09319) since 2009. For about the last 3 years it was in storage and I recently unpacked and powered it up again (12V switchmode wall-wart). As soon as I flipped the power switch the 100µ tantalum exploded in my face (always wear safety goggles!). It was a yellow-brown cap, unfortunately now I'm unable to identify it further.

    Anyhow, managed to squeeze in a polymer aluminium in it's place (quite tight). Powered it up and it's working fine. PTC must have done it's job.

    Anyone else seen that? Long periods of storage fatal to tantalums?

  • Member #362523 / about 11 years ago / 1

    Why is this not working to power my Raspberry Pi (without peripherals)? I'm inputing 12V, 1A, and the RPi power lights come on, and go off, then on.... but it never fully starts up. When I plug a 5V adapter directly into the pi, it works fine. What's going on??


    • M-Short / about 11 years ago / 1

      I'm guessing its not getting enough power. I don't know if the Pi pulls more than 800mA at startup, or if 4.9W (12V-5V *700mA) of heat dissipation is too much for this chip without a heat sink. If you have any other questions feel free to email us at

      • Member #362523 / about 11 years ago / 1

        I think my power supply stick is defective. I've tried many different power supplies an the second set of output pins. I've managed to use an arduino to step down the voltage into the Raspberry and it works fine. It just will not work through the power supply stick.

  • Member #439214 / about 11 years ago / 1

    to connect the power supply to a breadboard can I use the same header strips (pins) that came with my Inventor's Kit?

  • Member #402281 / about 11 years ago / 1

    Can I run this off of 24VDC? Looking at the LM317 voltage regulator specs and the schematic link above, I don't see any reason it can't do 24V. I suppose the extra voltage drop may result in extra dissipation in the VR, but I'm only pulling about 30ma max anyway. But I need to control a 24VCD solenoid with a circuit I'm tinkering on. Well, I guess I'll just try it out.

  • Member #402281 / about 11 years ago / 1

    I had this in a little cardboard box in my luggage on a flight recently, and the power switch broke off. I suppose it could have been jostled too much but it wasn't with anything heavy in the box. I just soldered a wire across the switch traces so it is fixed to on. It is very handy to have for breadboarding.

  • BillMurray / about 13 years ago * / 1

    Another option

    coming from China, but the price is right.

    edit: Got one of these and it is awesome.

    up to 4A, 1.5-30v out.

    5-35v in.

    current adjustable.

    no detectable heat at 5v, 1A

  • DGallagher / about 13 years ago / 1

    Since this is an open source product... is there a component list somewhere with the component sizes for footprint? Size example: SMD resistor 1206 footprint

    • Pearce / about 13 years ago / 1

      The eagle files will specify the component sizes of the different components.

  • Drew2 / about 13 years ago / 1

    How much current can this supply for each output when connected to a 12V power supply? This looks like a nice product, but is missing a couple of key specs. It would also be nice to know the specs of the PTC.

  • BB / about 13 years ago / 1

    Fifteen bucks is a bit steep for one of the simplest and cheapest linear regulator circuits, and using cheaper SMD parts to boot. I thought the other breadboard power supply was overpriced, but this is like $5 worth of parts here. A switching wall wart, that you have to buy for this anyway, will usually provide nearly as clean power anyway, for far less cost.
    Yeah "convenience", but this board doesn't even have nice and easy to use switches, or any special useful features to set it apart, like two independent voltage-selectable power rails from the same board, or an efficient bucking/boosting circuit, or something like that.

    • Ok since sparkfun doesnt mind competition i though id post a link or 2 here...

  • Don101 / about 13 years ago / 1

    Nice looking unit, but I'm not seeing the max Iout. What's it rated?

  • Why do you guys sell things so expensive? I mean i have one here with USB to UART and POWER for the same price...

    • We love competition and we're always trying to reduce costs (hence the board mod). It's great to see different products out there. I believe our boards are higher quality with better testing and manufacturing. It results in a cleaner overall experience. Then again, we're just debating a breadboard power supply.

  • Mulvane / about 13 years ago / 1

    Would like to see this with 4 pins on either side to help stabilize it more. Also, a terminal block where the 2 pin header is would be a welcome addition. Other than that, nice little board for basic breadboard power.

  • What changed?

    • Kamiquasi / about 13 years ago / 1

      From (PRT-09319) ..
      Replacement: PRT-10804. We've made some minor changes to this board layout to prevent the barrel jack from hanging over the edge. This page is for reference only.
      The pictures haven't been updated to reflect this, apparently. However, the Eagle files are also available, and we can compare them in more detail.
      The schematic is largely unchanged. A missing VIN label was added and v13 changes for the overall design noted. They are:
      * updated FP on barrel jack to use larger drill holes, (the previous FP was too tight and didn't allow part to sit flush on PCB)
      * moved barrel jack up to avoid overhang
      * changed to 0603 FPs
      The board has seen more changes as the barrel jack moving up meant rotating F1 and moving it to to the left, which meant D1 had to move down. You can see the change to 0603 footprints on the right half of the board. C2 in the top right got a bit of extra silkscreen.

      • Kamiquasi / about 13 years ago / 1

        Ran out of space, but for those of you who have read.. might see Nathan being Nathan in this board change :)
        --- spoiler ---
        "I have been known to move a via to avoid a label as well, but that's just me." - Nate
        Observe via in the middle of the board having been moved down to accommodate the new power jack silkscreen position.

        • Hah! I wish I could claim responsibility for this, but it's actually the team doing really good things. If you think about when these are panelized 3x3, if any connector hangs over the edge, that connector bumps the parts on the next board over so you have to add space in between boards on the panel, wasting PCB space. They mod'd the board so that we more efficiently utilized PCB real estate. How's that for execuspeak?

          • Kamiquasi / about 13 years ago / 1

            Then perhaps you taught them well ;)
            It does make sense wrt panelization+pnp, but it makes sense for the end-user as well.. things unnecessarily jutting out is no bueno :)

    • Kes / about 13 years ago / 1

      They didn't post it on this page, only on the former part's page, but they moved the power jack position a bit so that it sits flush, instead of having a bit of overhang.

Customer Reviews

5 out of 5

Based on 3 ratings:

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1 of 1 found this helpful:

I soldered the headers onto the power supply PCB, connected a 12VDC power cube to the power jack and it worked. A person can't ask for any more than that...

What I really like about this proto-board design is that, the headers are correctly placed and allow for the power buss in each side of the proto-board to receive power.

This proto-board power supply is well worth the money.

Definitely worth it

Very sturdy and reliable - not cheaply made. And if you want it to sit flat and stable just connect it about 5 spots in from the edge and put a dummy female header somewhere under the other side.

Always seem to need more power.

I like the ideas behind the updated version for stability. Sparkfun makes it a habit of building their boards rugged and well thought out. This product is no different, it will do you well.