Feather 328P - Atmega328P 3.3V @ 8 MHz Adafruit Feather 328P - Atmega328P 3.3V @ 8 MHz is a development board for the classic 'Arduino' chip ATmega328P. The Feather 328P is thin, light, and sets a new standard for portable microcontroller cores. The ATmega328P is clocked at 8MHz and at 3.3V logic. At the Feather 328P's heart is an ATmega328P clocked at 8 MHz and at 3.3V logic, a chip setup the same as the Pro Mini and similar to the Adafruit Metro 328. This chip has 32K of flash and 2K of RAM and is paired with a SiLabs CP2104 to give it a built-in USB-to-Serial program and debug capability.