ATMEGA16U4-AU Atmel, ATMEGA16U4-AU Datasheet - Page 425

• Manufacturer Part Number: ATMEGA16U4-AU
• Description: MCU AVR 16K FLASH USB 44TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA16U4-AU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 26
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Processor Series: ATMEGA16x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 1.25 KB
• Interface Type: SPI, TWI, USART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 26
• Number Of Timers: 5
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 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, 12 Channel
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table of Contents
7766F–AVR–11/10
1
2
3
4
5
6
Pin Configurations ................................................................................... 3
Overview ................................................................................................... 3
About ......................................................................................................... 8
AVR CPU Core .......................................................................................... 9
AVR ATmega16U4/ATmega32U4 Memories ........................................ 18
System Clock and Clock Options ......................................................... 27
2.1Block Diagram ...........................................................................................................4
2.2Pin Descriptions ........................................................................................................5
3.1Disclaimer ..................................................................................................................8
3.2Resources .................................................................................................................8
3.3Code Examples .........................................................................................................8
3.4Data Retention ..........................................................................................................8
4.1Introduction ................................................................................................................9
4.2Architectural Overview ..............................................................................................9
4.3ALU – Arithmetic Logic Unit ....................................................................................10
4.4Status Register ........................................................................................................11
4.5General Purpose Register File ................................................................................12
4.6Stack Pointer ...........................................................................................................13
4.7Instruction Execution Timing ...................................................................................14
4.8Reset and Interrupt Handling ..................................................................................15
5.1In-System Reprogrammable Flash Program Memory .............................................18
5.2SRAM Data Memory ...............................................................................................19
5.3EEPROM Data Memory ..........................................................................................21
5.4I/O Memory ..............................................................................................................26
6.1Clock Systems and their Distribution .......................................................................27
6.2Clock Sources .........................................................................................................28
6.3Low Power Crystal Oscillator ...................................................................................29
6.4Low Frequency Crystal Oscillator ............................................................................31
6.5Calibrated Internal RC Oscillator .............................................................................32
6.6External Clock .........................................................................................................33
6.7Clock Switch ............................................................................................................34
6.8Clock switch Algorithm ............................................................................................35
6.9Clock Output Buffer .................................................................................................37
ATmega16/32U4
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