The ATmega8A is a low-power CMOS 8-bit microcontroller based on the AVR RISC architecture. By executing powerful instructions in a single clock cycle, the ATmega8A achieves throughputs approaching 1 MIPS per MHz, allowing the system designer to optimize power consumption versus processing speed.

• High-performance, Low-power AVR® 8-bit Microcontroller
• Advanced RISC Architecture
• 130 Powerful Instructions - Most Single-clock Cycle Execution
• 32 x 8 General Purpose Working Registers
• Fully Static Operation
• Up to 16 MIPS Throughput at 16 MHz
• On-chip 2-cycle Multiplier
• High Endurance Non-volatile Memory segments
• 8K Bytes of In-System Self-programmable Flash program memory
• 512 Bytes EEPROM
• 1K Byte Internal SRAM
• Write/Erase Cycles: 10,000 Flash/100,000 EEPROM
• Data retention: 20 years at 85°C/100 years at 25°C
• Optional Boot Code Section with Independent Lock Bits
• In-System Programming by On-chip Boot Program
• True Read-While-Write Operation
• Programming Lock for Software Security
• Peripheral Features
• Two 8-bit Timer/Counters with Separate Prescaler, one Compare Mode
• One 16-bit Timer/Counter with Separate Prescaler, Compare Mode, and Capture Mode
• Real Time Counter with Separate Oscillator
• Three PWM Channels
• 8-channel ADC in TQFP and QFN/MLF package
• Eight Channels 10-bit Accuracy
• 6-channel ADC in PDIP package
• Six Channels 10-bit Accuracy
• Byte-oriented Two-wire Serial Interface
• Programmable Serial USART
• Master/Slave SPI Serial Interface
• Programmable Watchdog Timer with Separate On-chip Oscillator
• On-chip Analog Comparator
• Special Microcontroller Features
• Power-on Reset and Programmable Brown-out Detection
• Internal Calibrated RC Oscillator
• External and Internal Interrupt Sources
• Five Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down, and Standby
• I/O and Packages
• 23 Programmable I/O Lines
• 28-lead PDIP
• Operating Voltages
• 2.7 - 5.5V
• Speed Grades
• 0 - 16 MHz
• Power Consumption at 4 Mhz, 3V, 25°C
• Active: 3.6 mA
• Idle Mode: 1.0 mA
• Power-down Mode: 0.5 μA