It’s blue! It’s thin! It’s the Arduino Pro Mini! SparkFun’s minimal design approach to Arduino. This is a 3.3V Arduino running the 8MHz bootloader. Arduino Pro Mini does not come with connectors populated so that you can solder in any connector or wire with any orientation you need. We recommend first time Arduino users start with the Uno R3. It’s a great board that will get you up and running quickly. The Arduino Pro series is meant for users that understand the limitations of system voltage (3.3V), lack of connectors, and USB off board.
We really wanted to minimize the cost of an Arduino. In order to accomplish this we used all SMD components, made it two layer, etc. This board connects directly to the FTDI Basic Breakout board and supports auto-reset. The Arduino Pro Mini also works with the FTDI cable but the FTDI cable does not bring out the DTR pin so the auto-reset feature will not work. There is a voltage regulator on board so it can accept voltage up to 12VDC. If you’re supplying unregulated power to the board, be sure to connect to the “RAW” pin on not VCC.
The latest and greatest version of this board breaks out the ADC6 and ADC7 pins as well as adds footprints for optional I2C pull-up resistors! We also took the opportunity to slap it with the OSHW logo.
Can’t decide which Arduino is right for you? Arduino buying guide!
Note: A portion of this sale is given back to Arduino LLC to help fund continued development of new tools and new IDE features.
This should only be done as a last resort
Most likely your board isn’t bricked, unless you have done something drastic like modified the fuses. In which case, reflashing the board probably won’t help you.
However, if you have no options left and want to try to reflash the bootloader with an Uno or RedBoard. Here are links to some tutorial to get you started:
(*Make sure to upload the ISP sketch to the programming board. Also, tie the VCC pin to the 5V pin of the RedBoard or Uno. This will set the chip on the Pro Mini to 5V without having to worry about any logic level conversion. Lastly, be sure to double check the board options you are selecting so that the Arduino IDE uses the correct bootloader hex file.)
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.
Skill Level: Rookie - The number of pins increases, and you will have to determine polarity of components and some of the components might be a bit trickier or close together. You might need solder wick or flux.
See all skill levels
If a board needs code or communicates somehow, you're going to need to know how to program or interface with it. The programming skill is all about communication and code.
Skill Level: Rookie - You will need a better fundamental understand of what code is, and how it works. You will be using beginner-level software and development tools like Arduino. You will be dealing directly with code, but numerous examples and libraries are available. Sensors or shields will communicate with serial or TTL.
See all skill levels
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.
Skill Level: Competent - You will be required to reference a datasheet or schematic to know how to use a component. Your knowledge of a datasheet will only require basic features like power requirements, pinouts, or communications type. Also, you may need a power supply that?s greater than 12V or more than 1A worth of current.
See all skill levels
Based on 43 ratings:
2 of 2 found this helpful:
I’m using this as an ADC to convert an analog pot into a digital value which is then input into a Raspberry Pi. I had a 9V battery in my project case, so I tried powering this board up using the 9V line on the RAW pin. The product description for this board says the max voltage on RAW is 12V (and the schematic says 16V), but as soon as I connected 9V to RAW, there was a loud “POP” and the bitter taste of disappointment (and melted plastic) in the air. Happily, it was only the regulator IC which blew, and I’m able to power and use the rest of the board using the 3.3V pin on the Raspberry Pi driving the Vcc line on the FTDI header.
Another great SparkFun product, but I still wonder what happened with the voltage regulator. Anyone had a similar experience?
1 of 1 found this helpful:
Really great product. Reasonable cost, documentation sufficient, and great compatibility with Arduino family. Low power consumption, too less than 10ma - that along with the small size and easy hook-up (flexible use of header pins if desired) makes this my go-to Arduino platform.
4 of 4 found this helpful:
So removing the solder blob allows you to run the board off a 3.7V lipo. from full charge(4.2V) to discharge (~3.2V) the microcontroller runs its 8MHz quite happily with no complaints. Does really well in deep sleep modes as well.
2 of 2 found this helpful:
With the possible exception of it’s 5V sibling, this is my favorite Arduino board. It’s small, it’s inexpensive, and it does everything one would expect of an Arduino.
1 of 1 found this helpful:
I really like this and the 5V version. For many projects I prefer them to the UNO. My only beef and the reason for the loss of a star is the fact that pins A4 and A5 are not on the outside of the board and worse, they are offset. So for I2C you have to run wire or build your own board. Not the worst thing ever, but for a tiny bit bigger of a footprint, I personally would have preferred those pins on the outside.
3 of 3 found this helpful:
This is perfect if you want to embed an Arduino into a small project. The 3.3v version is awesome as you can directly connect to things like the small WiFi and nRF24 radio boards that are native 3.3v chips - no need for the Sparkfun 5-3.3v converter board.
Make sure you pick up a FTDI 3.3v logic board or cable. The 5v one you probably have lying around won’t do you any good with this board.
2 of 3 found this helpful:
Some of our local amateur radio folks (aka Hams) are supporting a climate change class taught at Williams College. Last year the class launched a balloon that reached 30K feet and we received telemetry data from the balloon. This year we plan to design a more capable payload for the balloon. The light weight, low cost, low power requirements, and availability of software make this product a great choice for generating telemetry data.
I’ve been using the Pro Mini boards since they were first introduced and they’re just the ticket if you need a super small Arduino board for your project. I like to keep a few of both 3.3V and 5V versions on my bench as they’re my go to board for quickly prototyping circuits.
I built my wife a birthday card using this board and some red LEDs. The Pro Mini is the perfect size to hide in a piece of cardboard along with all the wiring and a coin battery. She loved the card.. I constantly look for opportunities to use one of these little guys.. Great product!
This low-voltage arduino can fit every tiny, cableless proyect you can imagine!
I’m currently hacking a PS2 remote controller, in order to use it to drive a RC DIY quadcopter. I emptied the controller, because I found the electronic inside very ugly, and wanted to make all the logic of the controller on my own. I like using Atmel microcontrolers, but I don’t have the skills to solder CMS ones: indeed, any DIP-24 package don’t fit in the controller. Then, the Pro Mini was the perfect board: it’s tiny enough to fit in, and there’s no need to CMS solder.
I seem to be collecting microcontroller boards and these are my newest acquisition.
I’ve used one of these very successfully in a micro/macrophotography stacking rig.
I power mine with 12V or 9V to the RAW pin. No smoke. If there is smoke, something is wrong with your unit or wiring. I always use these with external reverse polarity protection diodes (Schottky) or even MOSFETs. It’s easier than you might think to wire things up backwards.
I am a bit perplexed, however, by the location of those four analogue input pins. I guess it makes the board a bit shorter by putting them there, but I’d rather a board that’s 5mm longer with those pins placed in-line with the others, two per side.
Another thing to note is that the silk-screening for the TX and RX pins is quite confusing unless you consult the ATMega328 pinout. Arduino UNO, for example, labels their pins TX->1 and RX<-0. Letting you know that TX (out) is pin 1, and RX (in) is pin 0. On this board, however, the pin numbers are missing - but to a casual observer, it may not appear that way. Instead, the letters I (in) and O (out) appear, which are easy to confuse with pin numbers. RXI is in fact pin 0, and TXO is in fact pin 1. So beware of that, if you plan to actually use those for something other than serial.
I bought 3/3V and 5 V versions of this and got an immediate download and run. Then they stopped taking downloads and it took 2 days to figure out what it was. In my circuit I was using one of the BT boards (Bluetooth) hooked up to the RX and TX pins. With that connected it will not program. Pull one of the two lines and it programs fine. It’s a little irritating but it works and the mini pro is the exact right size and does a great job. The only other thing I can say is that you can’t easily hook A4 and A5 to your breadboard if you want to use I2C. You have to solder wires in to A4 and A5 and plug the rest into your breadboard then plug the wires from A4 and A5 into your breadboard. A little irritating but if they were outside then the board would be bigger and it would not fit what I need. Overall I am happy with the mini pros I bought.
Hi, You’ll commonly want to disconnect any devices from your hardware serial when programming. The trick is to run software serial for your Bluetooth device. That will move the communication lines over to non hardware UART lines and will allow you to leave the BT hooked up when programming.
I’ve basically abandoned all Arduino models except this and the Moteino (which is basically a Pro Mini with a radio). I haven’t done a project that needed a larger processor or more IO, and for $10, you can make a lot of really cool stuff!
The biggest problem with Sparkfun boards is, the AREF missing!!! So don’t buy it if you want to scale the sensor readings or to improve the resolution of your measurement.
This is a great way to get an MCU into a tiny project based on the easy-to-use Arduino platform. It’s very powerful and has the same numnber of i/o pads as the big boards. Getting the program on is a bit tricky, but not too terrible once you have the right set-up.
I really like it. It is the best Arduino board for the small size projects. I recommend this product.
0 of 1 found this helpful:
I was spending a lot of time trying to figure out why I couldn’t get the Serial1 port to work as it kept screwing up and hanging the Serial data also. I finally looked at the specs and noticed that it has only one UART which is the same as the FTDI port. Actually it doesn’t make sense to me. Why would there be wasted RX and TX when they are the same as the RX and TX on the FTDI?
The Pro Mini either in 3V or 5V is my goto Arduino when I don’t need the traditional form factor for shields. They are just the thing for building into zombie costumes or tiny robots. These Sparkfun Pro Minis and well made and well supported.
I still could not believe the low current it takes in power down mode. (I hope I use the board correctly to measure the ultra low power down mode current) It is ~200 nA with out the power LED. I have seen others do many changes to the board to get 4.5uA, but just removing only the LED I was able to get it down to ~200NA. It is probably due to MIC5205 Vreg the board. Great Product, love it.
Yes, there’s some additional educational overhead because it has less onboard, so this shouldn’t be your first arduino. But! It’s tiny and uses less power (good for batteries), and fits into wee little projects. This is my go-to device for my embedded systems projects, though I tend toward the simple, so I’m not driving huge light arrays or anything requiring a lot of computational horsepower. I mostly do small art projects or simple detectors. For those, this thing is way more than enough functionality.
This is the perfect little device, great for miniaturizing your projects. It did take me a while to figure out how to program (if programming with an Uno, for instance, you have to remove the ATmega).
Easy to get up and running with these guys, sufficient memory, compatible with a ton of 3.3V devices without the need for level shifting…same reasons everyone else loves them…and they aren’t expensive at all…
The Pro Mini is a powerful tool in an incredibly small footprint. It took me a bit to get going with it but there really are no great mysteries to solve. Just carefully follow the “Getting Started Tutorial” and you’ll be fine, even if you’re a newbie like me. For the price this little device can’t be beat!
The Arduino Pro Mini is a very powerful Arduino with lots of features and I/O in a very small package. If you need an Arduino that is physically small or has to run on batteries/low power this is a great choice. This comes in a 5v and 3.3v version, as well as an 8 or 16 MHz option.
One typical usage might be a remote sensor that needs to report data (say temperature or weight) occasionally. The Pro Mini may wake occasionally from h/w powerdown, power up a radio, report the data and then powerdown again. Depending on the factors you might be able to run a year or more on AA batteries.
The Pro Mini comes without headers (you need to add your own) and without a USB connector, so to program it you will need Sparkfun’s serial adapter for that. Although it’s small it does come with a voltage regulator that can feed peripherals as well as a handy reset button.
Note for ultra low power applications there are many tricks you can find online such as removing the power LED as well as the voltage regulator (assuming you don’t need these). Removing one or both of these can have substantial impact on battery life.
Overall it’s a great Arduino in a tiny package!
If you need to reduce the size or power of your project, graduate from the Arduino Pro to this board. Possible to power the MCU directly bypassing the on-board regulator if low power is the goal. I wish the LED wasn’t on an SPI pin, but that’s the same with the larger board too.
Perfect for my various embedded projects, and at amazingly low cost.
i find that the “Sketch” programming approach used by the Arduino folks is great for most applications, but that the ability to embed lower-level code in the applications is also helpful for specialized applications, and, if necessary, to reduce application footprint and save flash space.
The flash capacity of this device (32 KB) is pretty good and having purchased a few of these from Sparkfun, the quality is excellent. I have never received a DOA device.
My current project is using this device and Sparkfun’s microSD level-shifting breakout to add an insane amount of storage (like 64GB) to an early 1980s industrial control Z80-based system that has just 16K RAM on board. Weird but fun. I have the hardware working and am developing the communication protocol and device driver routines.
I have also used this device with environmental sensors in a musical training application, where the device and sensors are embedded -within- a medieval instrument to provide wireless, real time feedback to the musician to help him/her improve their playing. Another “weird but fun” thing.
Versatile, I have used both the 3.3V and 5V versions for projects ranging from replacing a Dan Foss fan controller in diesel motorhomes to solar control to smart on/off switch functions in motorhomes.
Easy to program and very reliable, and cheap, what more could anyone ask?
Using it to miniaturize an Uno/ESP8266 design. Great partnership!
We apply it in academic experiment with Smart Sensors.
I’ll give these a “5”. With 4 smallish projects planned, these were “on sale” so I snatched up 5 (but two were the 5 volt version). Been using these for a few years, and they work better for my projects than an official size Arduino.
Minimal soldering easy programming multitude of great library’s.
I use it for almost my project, I cannot imagine how I could do all I do without it. Its key-feature is the size. You can put it almost everywhere.
What is in my dreams? To have the Pro Mini with a larger built-in RAM. Sometimes 32K of flash memory can be a limit.
This is a great, affordable breakout board for my home automation and sensor project. It’s very easy to breadboard or place into a PCB of my own making or even stripboarding. It’s very easy to program and has more power than I need, I particularly like the lower voltage requirements over the 5.0 volt board. The fact that I bought them on sale for half price makes them particularly attractive.
is there anything better than this tiny, easy to use computer?
Works exactly like it should so 5 stars.
these are awesome little development boards. Highly recommend the FTDI breakout programmer, makes life very easy. This board is very thin, compact, and has plenty of IO options. Easy to solder.
Of course it’s awesome, it’s from Sparkfun.
Useful as low-cost and already-wired processor in testing data communication (RS232) programming with a PC serial port by assembly-language and by the Arduino IDE
If you need to integrate a small ready-to-use arduino/ATmega in your project this is a pretty great little board. this is made to be as small as portable as possible. Even the PCB itself is thinner then usual.