Designation = Atmel Technology = Trinket mini microcontroller board Processor part number = ATtiny85 Processor type = MCU You can program the Trinket the via the Arduino IDE, but it is not 100% compatible with the Arduino. Adafruit Trinket Mini Microcontroller. The Adafruit Trinket is now available in its second generation - with even more power packed into a board about the size of a postage stamp. It features an Atmel ATtiny85 processor with 8K of flash memory and 5 I/O pins. Thanks to its USB bootloader, it can be easily connected to any computer and reprogrammed just like an Arduino. It cannot be expanded with an Arduino Shield, but for many simple, small portable or wearable projects, the Trinket can be the perfect platform. This latest version has a micro-USB connector thinner, so it has a reset button and 2 LED indicators. The Trinket is available in two versions: - Adafruit Trinket 3.3 V (8 MHz) (RS ; 124-5509 124-5509 ) - Adafruit Trinket 5 V (8 or 16 MHz) (RS ; 124-5506 124-5506 ) Both versions work the same, but differ in the voltage of operation logic. Up to 16 V input voltage, reverse polarity protection, thermal and current limit protection. - Built-in green power LED and red pin 1 LED - Reset button to invoke bootloader or restart program - 5 GPIO - 2 shared with USB interface. The three independent I/O pins also have an analog input and two PWM outputs. The 2 shared I/O pins have 2 more analog inputs and one more PWM output. - Hardware I²C/SPI functions for branch and sensor connection. - Works with many basic Arduino libraries including Adafruit Neopixel - 2 mounting holes.