ATmega8A Atmel Corporation, ATmega8A Datasheet - Page 3

• Manufacturer Part Number: ATmega8A
• Manufacturer: Atmel Corporation

Specifications of ATmega8A

• Flash (kbytes): 8 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 12
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 23
• Ext Interrupts: 2
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 1
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Pwm Channels: 3
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

2. Overview
2.1
8159D–AVR–02/11
Block Diagram
The Atmel
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.
Figure 2-1.
RESET
GND
VCC
®
AGND
AREF
AVR
Block Diagram
®
ATmega8A is a low-power CMOS 8-bit microcontroller based on the AVR
INSTRUCTION
INSTRUCTION
AVR CPU
PROGRAMMING
CONTROL
PROGRAM
PROGRAM
REGISTER
DECODER
COUNTER
FLASH
LINES
PORTC DIGITAL INTERFACE
MUX &
PORTC DRIVERS/BUFFERS
LOGIC
ADC
+
-
PC0 - PC6
REGISTERS
INTERFACE
INTERFACE
PURPOSE
REGISTER
GENERAL
POINTER
STATUS
STACK
COMP.
SRAM
ADC
ALU
SPI
X
Y
Z
OSCILLATOR
WATCHDOG
COUNTERS
INTERRUPT
MCU CTRL.
INTERNAL
& TIMING
EEPROM
TIMERS/
USART
TIMER
PORTB DIGITAL INTERFACE
PORTD DIGITAL INTERFACE
PORTD DRIVERS/BUFFERS
PORTB DRIVERS/BUFFERS
UNIT
TWI
PB0 - PB7
PD0 - PD7
OSCILLATOR
OSCILLATOR
ATmega8A
XTAL1
XTAL2
3