Attiny85 Digispark Development Board

Shrink your Arduino projects right down to a tiny board. Fully compatible with most Arduino code, the ATTiny is the smallest possible Arduino, due to its size there are only 6 IO pins available (2 are shared with USB)

The ATTiny only has 8Kb of memory and 3 PWM pins

Note

This has 5v logic, so make sure a logic leveller is used when interfacing with 3.3v microchips or sensors

Featuring;

Atmel ATTiny85 microcontroller

6 Digital Input/Outputs (2 are used for USB only if your program actively communicates over USB, otherwise you can use all 6 even if you are programming via USB)

8k Flash Memory (about 6k after bootloader)