The Adafruit Feather 32u4 board is based on an Atmel ATmega32u4 microcontroller, which is operated with 3.3 V and clocked with 8 MHz. The chip has 32 KB of flash memory, 2 KB of RAM and an integrated USB controller, so that no FTDI is required for the serial connection, for example. Ideal for mobile applications! The board has a connection for 3.7 V LiPo batteries and a charging circuit. The board can be operated and the battery can be charged via the microUSB port. The Feather 32u4 Basic Proto automatically switches from battery to USB operation when the board is connected via USB. The battery voltage can be measured via an analog input on the board. Comes fully tested with USB bootloader for use with the Arduino IDE and pin headers. The pin headers can be soldered on by you if necessary.
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