ATMEGA644-20MU

The ATMEGA644-20MU is a high-performance, low-power 8-bit 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, real time counter, three flexible timers/counters with compare modes and PWM, 2 USARTs, byte oriented 2-wire serial interface, 8-channel/10-bit A/D converter with optional differential input stage with programmable gain, programmable watchdog timer with internal oscillator, SPI serial port, JTAG (IEEE 1149.1 compliant) test interface for on-chip debugging and six software selectable power saving modes. The device operates between 2.7 to 5.5V. By executing powerful instructions in a single clock-cycle, the device achieves throughputs approaching 1MIPS per MHz, balancing power consumption and processing speed.

• Advanced RISC architecture
• Power-on reset 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
• 131 powerful instructions-most single clock cycle execution
• 32 x 8 general purpose working registers
• Fully static operation
• Up to 20MIPS throughput at 20MHz
• JTAG (IEEE std. 1149.1 compliant) interface
• Programmable watchdog timer with separate on-chip oscillator
• On-chip analogue comparator
• Interrupt and wake-up on pin change
• Two 8-bit timers/counters with separate prescaler and compare mode
• One 16-bit timer/counter with separate prescaler, compare mode and capture mode
• Real-time counter with separate oscillator
• Six PWM channels
• One programmable serial USART
• Serial peripheral interface (SPI)