ATMEGA48-20AI Atmel, ATMEGA48-20AI Datasheet - Page 369

• Manufacturer Part Number: ATMEGA48-20AI
• Description: IC AVR MCU 4K 5V 20MHZ 32-TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA48-20AI

• 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: 4KB (2K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-TQFP, 32-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: ATMEGA48-24AI; ATMEGA48-24AI

Table of Contents
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2545S–AVR–07/10
Features ..................................................................................................... 1
Pin Configurations ................................................................................... 2
Overview ................................................................................................... 5
Resources ................................................................................................. 7
Data Retention .......................................................................................... 7
About Code Examples ............................................................................. 7
AVR CPU Core .......................................................................................... 8
AVR Memories ........................................................................................ 16
System Clock and Clock Options ......................................................... 26
1.1Pin Descriptions .........................................................................................................3
2.1Block Diagram ...........................................................................................................5
2.2Comparison Between ATmega48, ATmega88, and ATmega168 .............................6
6.1Overview ....................................................................................................................8
6.2Architectural Overview ...............................................................................................8
6.3ALU – Arithmetic Logic Unit .......................................................................................9
6.4Status Register ........................................................................................................10
6.5General Purpose Register File ................................................................................11
6.6Stack Pointer ...........................................................................................................12
6.7Instruction Execution Timing ...................................................................................13
6.8Reset and Interrupt Handling ...................................................................................14
7.1Overview ..................................................................................................................16
7.2In-System Reprogrammable Flash Program Memory .............................................16
7.3SRAM Data Memory ................................................................................................18
7.4EEPROM Data Memory ..........................................................................................19
7.5I/O Memory ..............................................................................................................20
7.6Register Description ................................................................................................21
8.1Clock Systems and their Distribution .......................................................................26
8.2Clock Sources .........................................................................................................27
8.3Low Power Crystal Oscillator ...................................................................................28
8.4Full Swing Crystal Oscillator ....................................................................................30
8.5Low Frequency Crystal Oscillator ............................................................................32
8.6Calibrated Internal RC Oscillator .............................................................................32
ATmega48/88/168
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