The Arduino Pro Mini Atmega328 5V/150mA 16MHz is a compact version of the Arduino, designed for projects where space is at a premium. It features the ATmega328 microcontroller running at 16MHz with an external quartz crystal for timing accuracy. 

Specifications:

• ATmega328 running at 16MHz with external resonator (0.5% tolerance)
• 0.8mm Thin PCB
• USB connection off board
• Supports auto-reset
• 5V regulator
• Max 150mA output
• Over current protected
• DC input 5V up to 12V
• On board Power and Status LEDs
• Analog Pins: 8
• Digital I/Os: 14
• PWM Pins : 6
• DC Current per I/O Pin : 40 mA
• Communication : UART , SPI , I2C
• Flash Memory : 32KB of which 2 KB used by bootloader
• SRAM : 2 KB
• EEPROM : 1 KB
• Clock Speed : 8 MHz (3.3V versions) or 16 MHz (5V versions)
• Dimensions are approximately 1.8 × 3.3 × 0.2 cm, and it weighs about 0.1 kg.

Learning Resources:

Arduino Pro Mini Documentation

Applications and Projects:

The Arduino Pro Mini is highly versatile, used in various applications including wearable technology, DIY electronics projects, compact devices, and educational purposes. Its small form factor makes it ideal for integrating into projects where space is limited. Common uses involve sensor networks, small robotics, and custom wearables, benefiting from its low power consumption and ability to run on battery power. Its programmability and range of digital and analog inputs/outputs support a wide array of peripherals and sensors, enabling a broad spectrum of hobbyist and educational projects.