Pro Micro 5V 16Mhz / 3.3V 8 Mhz Mini Leonardo Microcontroller Development Board For Arduino
Very small footprint which is very good for IOT implementation.

Description:

This microcontroller development board has 4 channel 10 bit ADC, 5 PWM pins, 12 DIO, and a hardware serial connection Rx and Tx you are familiar with. Running on 16MHz and 5V, this board will remind you a lot of other Arduino compatible boards that you like. There is a voltage regulator on board, so it can accept up to 12V DC. If you are supplying an unstable power supply board, be sure to connect to the "RAW" not on the VCC pin. Also a PTC fuse and diode protection is added to the power circuit.

Feature:

- ATMEGA32U4 running in 5V / 16MHz or 3.3V / 8MHz (please select in option)
- Micro USB interface programming on the board
- Four 10-bit ADC pin
- 12 digital I / O (5 PWM capability)
- Rx and Tx hardware serial connection
- Dimension : 33.2mm * 17.8mm * 5mm