ATMEGA8 Datasheet(PDF) – ATMEL Corporation

Overview
The Atmel®AVR® ATmega8 is a low-power CMOS 8-bit microcontroller based on the AVR RISC architecture. By executing powerful instructions in a single clock cycle, the ATmega8 achieves throughputs approaching 1MIPS per MHz, allowing the system designer to optimize power consumption versus processing speed.

Features
• High-performance, Low-power Atmel®AVR® 8-bit Microcontroller
• Advanced RISC Architecture
   – 130 Powerful Instructions – Most Single-clock Cycle Execution
   – 32 × 8 General Purpose Working Registers
   – Fully Static Operation
   – Up to 16MIPS Throughput at 16MHz
   – On-chip 2-cycle Multiplier
• High Endurance Non-volatile Memory segments
   – 8Kbytes of In-System Self-programmable Flash program memory
   – 512Bytes EEPROM
   – 1Kbyte Internal SRAM
   – Write/Erase Cycles: 10,000 Flash/100,000 EEPROM
   – Data retention: 20 years at 85°C/100 years at 25°C(1)
   – 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, 32-lead TQFP, and 32-pad QFN/MLF
• Operating Voltages
   – 2.7V – 5.5V (ATmega8L)
   – 4.5V – 5.5V (ATmega8)
• Speed Grades
   – 0 – 8MHz (ATmega8L)
   – 0 – 16MHz (ATmega8)
• Power Consumption at 4Mhz, 3V, 25C
   – Active: 3.6mA
   – Idle Mode: 1.0mA
   – Power-down Mode: 0.5µA