This is the well known Atmel’s ATmega328 microcontroller in a DIP-28 package. It has 32KB of flash and 2KB of RAM. It runs at 20MHz and has 23 I/O lines. 6 of these lines can be used as a 10 bit ADC.

Plenty of peripherals, including UART, SPI and I2C and 1024 bytes of EEPROM.

If you are looking for a direct replacement for the Arduino UNO, you need the ATmega328P-PU version.

Features

• 8-bit AVR microcontroller.
• Runs at 20MHz with external oscillator.
• 32KBytes of In-System Self-Programmable Flash program memory
• 1KBytes EEPROM
• 2KBytes Internal SRAM
• SPI, UART and I2C

Documents

• ATmega328 Datasheet