
Arduino Micro
Dev Board
Smallest official Arduino with native USB, based on ATmega32u4 at 16 MHz. Breadboard-friendly at 48×18mm with 20 I/O pins, 12 analog inputs, and USB HID/CDC emulation capability.

Adafruit Trinket 3.3V
Dev Board
Tiny 27×15mm Arduino-compatible microcontroller board with ATtiny85 at 8 MHz, 3.3V logic, 8KB flash, 3 GPIO pins, and Micro USB programming for minimal space-constrained projects.

Adafruit Trinket 5V
Dev Board
Tiny 31×15mm Arduino-compatible microcontroller with ATtiny85 at 8–16 MHz, 5V logic, 8KB flash, 3 GPIO pins, and Micro USB — the 5V variant for interfacing with 5V sensors and NeoPixel LEDs.

Adafruit Pro Trinket 5V
Dev Board
Compact ATmega328P-based Arduino-compatible board at 16 MHz, 5V, with 28KB flash, 18 GPIO, Micro USB, FTDI header, and mounting holes — a miniaturized UNO with battery-friendly power management.
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