Description: Here at SparkFun, we refuse to leave ‘good enough’ alone. That’s why we’re adding to our line-up of Arduino-compatible microcontrollers once more! The Pro Micro is similar to the Pro Mini except with an ATmega32U4 on board. The USB transceiver inside the 32U4 allows us to add USB connectivity on-board and do away with bulky external USB interface.
This tiny little board does all of the neat-o Arduino tricks that you’re familiar with: 9 channels of 10-bit ADC, 5 PWM pins, 12 DIOs as well as hardware serial connections Rx and Tx. Running at 8MHz and 3.3V, this board will remind you a lot of your other favorite Arduino-compatible boards but this little guy can go just about anywhere.
This is the 3.3V version so, as always, keep in mind the limits of system voltage and so forth. The lower system voltage also has its advantages, though, like ease of use with many common 3.3V sensors. 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.
Not sure which Arduino or Arduino-compatible board is right for you? Check out our Arduino Buying Guide!
Note: See the GitHub link below for support with the Arduino IDE.
Based on 13 ratings:
1 of 1 found this helpful:
Fantastic board. Amazingly compact and powerful for its incredibility small size. Very low power requirements. 1 LiPo cell will power it.
1 of 1 found this helpful:
I used it to drive remote controls, connected to an Nrf24L01 and a couple of pots and buttons. Works very well and lasts a long time with a regular 9v battery.
1 of 2 found this helpful:
I have only had it for a few weeks so I cannot give a long term evaluation opinion but a few things surface pretty quickly. Initial setup was a bit bumpy but the documentation on the website explains all and you only have to follow thoroughly. The unit is small, light, provides decent functionality. The main issues I have with the unit so far: The micro USB connector… what went wrong there ? This must be the crappiest connector available on the market. I don’t even dare to remove the USB cable once it was plugged in. This connector will undoubtedly rip off the PCB after a few connects/disconnects. In expectation of that it would have been helpful to have the D+ and D- pins broken out so I can access them via header, but no. If this connector comes off it gets messy. Second.. What is the deal with those 5 pins that are not broken out and marked Not Used in the schematic ? I’d rather have access to those pins and have the PCB slightly larger than the way it is now. Timer 0 would be nice to use with two compare outputs (OC0A and OC0B or PB7 and PD0) but one of them is not broken out… Why ? It is still a nice unit but those two issues bother me already. So much for now.
I love the small form factor and native USB support. I’ve got mine acting as an I2C slave receiving commands from a Raspberry Pi.
Software set up and uploading was pretty straightforward, and it does its job well. - main issue is the flimsy micro USB connector, have to be extremely careful with it
Note for Ubuntu 14.04 users have to add some udev rules so that your OS doesn’t mistake the Pro Micro for a GSM modem (https://forum.arduino.cc/index.php?topic=217910.0)
We’ve tried many different Micro USB connectors to try to resolve the risk of popping the jack off the board. Unfortunately this tiny connector can be very hard to keep stable with such little solder points and without being in a enclosure designed to support the jack. One tip is to carefully tack the jack down with some hot glue. This will at least help support the jack better.
Using 10 of these for a handheld RFID inventory project (SPI interface to RFID chip and also USB serial to labview application). During programming the serial port disconnects from the driver then reconnects, sometimes causing my windows environment to change the port ID, a minor annoyance and only during programming. The MISO/MOSI/CLK/SS pins are different from other arduino IC variations but located same place on the pcb. To avoid damaging the micro USB connector we use a second USB chassis mounted jack on the handheld case we designed. Overall a good project board for inexpensive 3.3v peripherals.
Compared to the more popular Arduino boards, this board is a perfect feature combination for battery-powered devices and for miniature devices. It runs on much less power giving a longer battery life, it accepts any voltage but it also accepts much lower voltage meaning fewer cells and more versatility. It’s power regulator is efficient, and it outputs regulated-3.3v to power the other components (which typically results in even more total power savings), and this also eliminates the need for level conversion circuitry (because it seems like everything is 3.3v these days). It’s significantly smaller than even the Arduino nano, and with the aforementioned fewer cells in the battery pack (due to that lower operating voltage), it allows either smaller batteries or greater capacity batteries. I also like the slimmer and more convenient/universal micro-USB connector, which works with standard phone cables.
The downside is that it seems the hardware serial RX TX pins share the USB serial, so when you are using the serial monitor to debug, you’re going to prevent the hardware serial from functioning. That can be pretty inconvenient, but a small price for the advantages, and I’ve had no problems using a soft serial connection instead. The chip’s on-board USB also causes my computer’s detected com port number to change during the upload/reboot sequence, which can also be annoying - it often adds more mouseclicks to the process, though doesn’t actually affect functionality in any way.
This is now my favorite board by far. If you’re making something that wants to be battery-powered or tiny or both, this seems like the clear frontrunner.
I received the board two weeks ago and it never worked. The board is not recognized at all. Sent an email Friday and still waiting to hear.
You ticket was received after Support was closed for the weekend. Someone will respond to your ticket as soon as possible.
This is the worst Arduino I have ever owned. It just makes your life miserable as you discover that the board does not program because the mini USB micro port disconnects the data lines every time it is touched. I bought two of these Pro Micros and the behavior is the same even with multiple USB cables.
The nail in the coffin is the driver. The serial port changes every time I program the board, so I have to re-select it each time. And this all happens when nothing is connected to the board.
Hmmm, that’s not normal behavior all for these boards. If you’re running a Mac with OS X, there may be some driver conflict there, but the data lines shouldn’t be disconnecting whenever the port is touched. I would recommend getting in touch with out tech support team, they should be able to assist you with your issues pertaining to this board.
I initially bought the pro micro 3.3v which worked for about 5 uploads then lost connection. Ho Yun “Bobby” Chan, provided excellent support. He got me a refund and recommended the pro mini with FTDI board which worked great. Great support, give Bobby a raise!!
Sorry you had an issue with your Pro Micro. I’m glad Bobby could help you out. He’s an awesome technician, and we appreciate his contributions to our Tech Support team. :) Thanks for the kind words.
0 of 1 found this helpful:
When I received it, I simply plugged it in and pulled out my iPhone. Using the official app I was able to simply connect to the device. Wonderful. Cannot wait to get making!
I haven’t used it extensively, but this cheap little board worked like a charm for all the small projects I have used it for. It’s tiny enough that you can embed it in any project, but it has enough broken out pins to to almost anything. Also the second hardware Serial proved to be really useful.
I purchased this back in April 2015 and just finally opened it up (Oct 2015). I developed a small system around the 5v one with a regulator for my 3v3 components (all of them). So I finally have an application now where the 3v3 one is a better fit (just a SATCOM updating system with a venus chip and a dense sensor board). Anyway, I pulled it out, soldered on headers, and plugged it in (alone first) - it didn’t even recognize. The power light shows but the serial port won’t show up and I don’t see any bad solders - note to self: try it before doing any soldering to at least know for the post mortem if I caused it or if it was DOA.
Probably my fault for waiting so long, and I am obviously long past being able to return/exchange it (totally valid). I’m sure the ones that work are great, I can attest to the 5v one being as awesome as most SF products are :)
EDIT: Looks like I left my settings on the 5v/16mhz one - so I’m pretty sure I caused it! Any one know how to reflash the bootloader on these?
Hi, Here’s instructions on how to recover a bricked pro micro. https://learn.sparkfun.com/tutorials/pro-micro–fio-v3-hookup-guide/troubleshooting-and-faq#ts-revive