Device Core = AVR / Data Bus Width Bit = 8 / Instruction Set Architecture = RISC / Family Name = ATmega644P / Clock Frequency Max. MHz = 20 / Program Memory Type = Flash / Program Memory Size KB = 64 / Data Memory Size KB = 2 / RAM Memory Size KB = 4 / Interfaces = 2x UART / Interfaces = 3x SPI / Interfaces = 1x I²C / ADC Channels = 8 / DAC Resolution Bit = 10 / Number of Programmable I/Os = 32 / Number of Timers/Counters = 3 / Supply Voltage Min. V = 2.7 / Supply Voltage Max. V = 5.5 / Operating Temperature Min. °C = -40 / Operating Temperature Max. °C = 85 / Package Type = PDIP / Pins = 40 / Mounting Type = Through Hole / Packaging = Tube / Length mm = 52.57 / Width mm = 15.24 / Height mm = 4.8