The Arduino Pro Mini is a microcontroller board based on the ATmega328. It’s designed to be a minimalistic and compact version of the Arduino Uno, with the main goal of being used in projects where space is a crucial factor. Here are the key features of the Arduino Pro Mini 5V 16MHz with the ATmega328:

1. Microcontroller: ATmega328
2. Operating Voltage: 5V
3. Input Voltage: 5-12V (recommended)
4. Digital I/O Pins: 14 (of which 6 provide PWM output)
5. Analog Input Pins: 8
6. DC Current per I/O Pin: 40 mA
7. Flash Memory: 32 KB (of which 2 KB is used by the bootloader)
8. SRAM: 2 KB
9. EEPROM: 1 KB
10. Clock Speed: 16 MHz
11. Size: 18 mm x 33 mm

Additional Notes:

• Programming: The Pro Mini does not come with a built-in USB interface for programming. You will need an external USB-to-serial adapter (or FTDI board) to upload sketches to the Pro Mini.
• Power: The board can be powered through the VCC and GND pins or through the RAW pin with a voltage between 5-12V.
• Bootloader: The Pro Mini comes with the Optiboot bootloader pre-installed, making it compatible with the Arduino IDE for easy programming.
• Configuration Options: The Pro Mini is available in 5V and 3.3V versions, and with different clock speeds (e.g., 8MHz). The specifications mentioned here are for the 5V 16MHz version.
• Size: Its compact size makes it suitable for projects with space constraints.