ATMEGA644A-AU Datasheet PDF - Microchip

●The ATMEGA644A-AU is a 8-bit high-performance AVR RISC-based Microcontroller combines 64kB ISP flash memory with read-while-write capabilities, 2kB EEPROM, 4kB SRAM, 32 general purpose I/O lines, 32 general purpose working registers, a real time counter, three flexible timer/counters with compare modes and PWM, two USARTs, a byte oriented 2-wire serial interface, an 8-channel 10-bit A/D converter with optional differential input stage with programmable gain, programmable watchdog timer with internal oscillator, SPI serial port, a JTAG (IEEE 1149.1 compliant) test interface for on-chip debugging and programming and six software selectable power saving modes. The device operates between 1.8 to 5.5V. By executing powerful instructions in a single clock cycle, the device achieves throughputs approaching 1 MIPS per MHz, balancing power consumption and processing speed.

● Advanced RISC architecture - On-chip 2-cycle multiplier

● High endurance, non-volatile memory segments

● QTouch® library support - Capacitive touch buttons, sliders and wheels

● JTAG (IEEE 1149.1 compliant) interface

● Peripheral features - Real time counter with separate oscillator

● Power-on reset (POR) and programmable brown-out detection

● Internal calibrated RC oscillator

● External and internal interrupt sources

● Six sleep modes - Idle, ADC noise reduction, power-save, power-down, standby and extended standby