ATMEGA325A-AUR Atmel, ATMEGA325A-AUR Datasheet - Page 676

• Manufacturer Part Number: ATMEGA325A-AUR
• Description: IC MCU AVR 32K FLASH 64TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA325A-AUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 54
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

iv
ATmega165A/165PA/325A/325PA/3250A/3250PA/645A/645P/645
18 SPI – Serial Peripheral Interface ......................................................... 159
19 USART ................................................................................................... 169
20 USI – Universal Serial Interface .......................................................... 198
21 AC - Analog Comparator ..................................................................... 210
17.4Counter Unit ........................................................................................................141
17.5Output Compare Unit ..........................................................................................142
17.6Compare Match Output Unit ................................................................................144
17.7Modes of Operation .............................................................................................145
17.8Timer/Counter Timing Diagrams .........................................................................149
17.9Asynchronous operation of the Timer/Counter ....................................................151
17.10Timer/Counter Prescaler ...................................................................................153
17.11Register Description ..........................................................................................154
18.1Features ..............................................................................................................159
18.2Overview .............................................................................................................159
18.3SS Pin Functionality ............................................................................................164
18.4Data Modes .........................................................................................................165
18.5Register Description ............................................................................................166
19.1Features ..............................................................................................................169
19.2Overview .............................................................................................................169
19.3Clock Generation .................................................................................................171
19.4Frame Formats ....................................................................................................174
19.5USART Initialization ............................................................................................175
19.6Data Transmission – The USART Transmitter ....................................................177
19.7Data Reception – The USART Receiver .............................................................180
19.8Asynchronous Data Reception ............................................................................185
19.9Multi-processor Communication Mode ................................................................188
19.10Examples of Baud Rate Setting ........................................................................189
19.11Register Description ..........................................................................................193
20.1Features ..............................................................................................................198
20.2Overview .............................................................................................................198
20.3Functional Descriptions .......................................................................................199
20.4Alternative USI Usage .........................................................................................205
20.5Register Descriptions ..........................................................................................206
21.1Analog Comparator Multiplexed Input .................................................................211
21.2Register Description ............................................................................................212
8285B–AVR–03/11