Update – Dec 16 2021:

Wow. 2021 supply-chain issues are making modern silicon harder to find. We’ve even had to see if we can dig up some antique ATMega328 to help the hacker community, and here they are, while they last!

The Atmel AVR ATmega328 is used as the heart of many Arduino / Freeduino microcontroller development boards. The ATmega328 runs pretty much the same speed, with same pinout, but features more than twice the flash memory (30k vs 14k) and twice the EEPROM (1Kb vs 512b) of the ATmega168.

This particular ATmega328P-20PU comes programmed and tested with Arduino Firmware which is ready to drop into any standard DIP-mount Arduino-compatible board, like our own Freeduino kits.

Please Note: This product now comes with the Arduino 1.0 optiboot bootloader programmed into it. When programming via the Arduino IDE please select “Arduino Uno” under the Tools -> “Board” category instead of “Arduino Duemilanove w/ ATmega328”. This bootloader not only has faster upload speeds but is now backwards compatible with products that use a FTDI USB-TTL converter chip.

The AVR series of microcontrollers are right up there with Microchip PIC products. Powerful, inexpensive, and programmable with some very good open source software (look up GCC), with a vibrant user community.

Here are more key features:

• 28 Pin narrow DIP package (0.3″)
• 32Kb byte self-programmable Flash
• 1Kb EEPROM
• 2048 byte internal SRAM
• Two 8bit timer
• One 16bit timer
• 6 Pulse-width modulators
• 6 10-bit analog-to-digital converters (ADC)
• 2 8-bit ADCs
• USART
• SPI
• WDT
• 23-programmable I/O lines
• Has lots of other neat TLAs (three-letter acronyms)