What's smaller than a Feather but larger than a Trinket? It's an ItsyBitsy! Small, powerful, Arduino-compatible - this microcontroller board is perfect when you want something very compact, but still with a bunch of pins.

ItsyBitsy 32u4 is only 1.4" long by 0.7" wide, but has 6 power pins, 6 analog & digital pins and 17 digital pins. It packs much of the same capability as an Arduino UNO. So it's great once you've finished up a prototype on a bigger Arduino, and want to make the project much smaller.

The ItsyBitsy 32u4 uses the Atmega32u4 chip, which is the same core chip in the Arduino Leonardo as well as the same chip we use in our Feather 32u4. The 5V 16 MHz It runs at the same speed and voltage of an Arduino UNO or Leonardo. The 3V 8 MHz version is the same speed and voltage as a Feather 32u4. So you'll be happy to hear that not only is Itsy Bitsy programmable using the Arduino IDE as you already set up, but a vast number of Arduino projects will work out of the box!

We recommend this as an upgrade from the Pro Trinkets because this has native USB so it will work with all computers, USB serial debugging, and a more reliable bootloader. You can even use the Pro Trinket LiPo backpack with this board to add recharge-able battery.

Here's some handy specifications:

• ATmega32u4 onboad chip in QFN package
• USB bootloader with a nice LED indicator, AVR109 compatible (same as Flora, Feather 32u4, Leonardo, etc)
• Micro-USB jack for power, USB uploading and debugging, you can put it in a box or tape it up and use any Micro USB cable for when you want to reprogram.
• Can act as a USB HID Keyboard, Mouse, MIDI or plain USB 'CDC' serial device (default)
• Power with either USB or external output (such as a battery) into VBAT pin - it'll automatically switch over
• On-board red pin #13 LED
• 23 GPIO total - 6 analog in, 1x SPI port, 1x I2C port, 1x Hardware Serial port and 10 more GPIO, 4 of which have PWM
• Can drive NeoPixels, connect to sensors, servos, etc.
• Reset button for entering the bootloader or restarting the program.

For the 5V version:

• 5V power and logic, 16MHz clock rate, 2KB RAM and 28K FLASH
• On-board 5.0V power regulator with 150mA output capability and ultra-low dropout. Up to 16V input, reverse-polarity protection, thermal and current-limit protection.
• Low current 3.3V regulator output from chip, for small sensors

For the 3V version:

We have two special pins on the 3V version of this board. There's a VHigh pin, this pin is a power pin whose voltage is the higher of VBAT and VUSB. We also made the digital #5 pin extra special on this board, it connects to a level shifter so it is only an output but the output is that 'high logic'. Basically what this means is if you want to drive NeoPixels, a picky servo, or a high-dropout-voltage LED from this board, and you want a 5V-logic-level output, this pin is the one you should use!

• 3.3V power and logic, 8 MHz clock rate, 2KB RAM and 28K FLASH
• On-board 3.3V power regulator with 500mA output capability and ultra-low dropout. Up to 6V input, reverse-polarity protection, thermal and current-limit protection.
• Special Vhigh output pin gives you the higher voltage from VBAT or VUSB, for driving NeoPixels, servos, and other high-current devices. Digital 5 level-shifted output for high-voltage logic level output.

Once headers are installed they can be fitted into 0.6" wide sockets