ATMEGA168-20PU Atmel, ATMEGA168-20PU Datasheet - Page 353

• Manufacturer Part Number: ATMEGA168-20PU
• Description: IC AVR MCU 16K 20MHZ 28DIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA168-20PU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 23
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 6x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-DIP (0.300", 7.62mm)
• Processor Series: ATMEGA16x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 1 KB
• Interface Type: 2-Wire, SPI, USART, Serial
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 23
• Number Of Timers: 3
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 6 Channel
• A/d Inputs: 6-Channel, 10-Bit
• Cpu Speed: 20 MIPS
• Eeprom Memory: 512 Bytes
• Input Output: 23
• Interface: I2C/SPI/UART/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 28-pin PDIP
• Programmable Memory: 16K Bytes
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 4.5-5.5 V
• Controller Family/series: AVR MEGA
• No. Of I/o's: 23
• Eeprom Memory Size: 512Byte
• Ram Memory Size: 1KB
• Rohs Compliant: Yes
• For Use With: ATSTK600-TQFP32 - STK600 SOCKET/ADAPTER 32-TQFPATSTK600 - DEV KIT FOR AVR/AVR32770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAGATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATAVRISP2 - PROGRAMMER AVR IN SYSTEMATJTAGICE2 - AVR ON-CHIP D-BUG SYSTEM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table of Contents
2545E–AVR–02/05
1
2
3
4
5
6
Features ..................................................................................................... 1
Pin Configurations ................................................................................... 2
Overview ................................................................................................... 3
About Code Examples ............................................................................. 6
AVR CPU Core .......................................................................................... 7
AVR ATmega48/88/168 Memories ........................................................ 15
System Clock and Clock Options ......................................................... 25
1.1Disclaimer ..................................................................................................................3
2.1Block Diagram ...........................................................................................................3
2.2Comparison Between ATmega48, ATmega88, and ATmega168 .............................4
2.3Pin Descriptions ........................................................................................................5
4.1Introduction ................................................................................................................7
4.2Architectural Overview ..............................................................................................7
4.3ALU – Arithmetic Logic Unit ......................................................................................8
4.4Status Register ..........................................................................................................9
4.5General Purpose Register File ................................................................................10
4.6Stack Pointer ...........................................................................................................11
4.7Instruction Execution Timing ...................................................................................12
4.8Reset and Interrupt Handling ..................................................................................12
5.1In-System Reprogrammable Flash Program Memory .............................................15
5.2SRAM Data Memory ...............................................................................................17
5.3EEPROM Data Memory ..........................................................................................18
5.4I/O Memory ..............................................................................................................24
6.1Clock Systems and their Distribution .......................................................................25
6.2Clock Sources .........................................................................................................26
6.3Low Power Crystal Oscillator ...................................................................................27
6.4Full Swing Crystal Oscillator ....................................................................................29
6.5Low Frequency Crystal Oscillator ............................................................................31
6.6Calibrated Internal RC Oscillator .............................................................................31
6.7128 kHz Internal Oscillator ......................................................................................33
6.8External Clock .........................................................................................................33
6.9Clock Output Buffer .................................................................................................34
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