ATXMEGA64A3-AU Atmel, ATXMEGA64A3-AU Datasheet - Page 24

• Manufacturer Part Number: ATXMEGA64A3-AU
• Description: MCU AVR 64K FLASH 1.8V 64-TQFP
• Manufacturer: Atmel
• Series: AVR® XMEGAr

Specifications of ATXMEGA64A3-AU

• Core Processor: AVR
• Core Size: 8/16-Bit
• Speed: 32MHz
• Connectivity: I²C, IrDA, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Number Of I /o: 50
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 1.6 V ~ 3.6 V
• Data Converters: A/D 16x12b; D/A 2x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP, 64-VQFP
• Processor Series: ATXMEGA64x
• Core: AVR8
• Data Bus Width: 8 bit, 16 bit
• Data Ram Size: 4 KB
• Interface Type: I2C, SPI, USART
• Maximum Clock Frequency: 32 MHz
• Number Of Programmable I/os: 50
• Number Of Timers: 7
• Operating Supply Voltage: 1.6 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8 bit, 2 Channel
• On-chip Dac: 2 bit, 1 Channel
• Package: 64TQFP
• Device Core: AVR
• Family Name: XMEGA
• Maximum Speed: 32 MHz
• For Use With: ATSTK600-TQFP64 - STK600 SOCKET/ADAPTER 64-TQFPATAVRONEKIT - KIT AVR/AVR32 DEBUGGER/PROGRMMRATSTK600-TQFP44 - STK600 SOCKET/ADAPTER 44-TQFP770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPIATAVRISP2 - PROGRAMMER AVR IN SYSTEM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

12.3.6
13. WDT - Watchdog Timer
13.1
13.2
8068T–AVR–12/10
Features
Overview
Software reset
The MCU can be reset by the CPU writing to a special I/O register through a timed sequence.
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The XMEGA A3 has a Watchdog Timer (WDT). The WDT will run continuously when turned on
and if the Watchdog Timer is not reset within a software configurable time-out period, the micro-
controller will be reset. The Watchdog Reset (WDR) instruction must be run by software to reset
the WDT, and prevent microcontroller reset.
The WDT has a Window mode. In this mode the WDR instruction must be run within a specified
period called a window. Application software can set the minimum and maximum limits for this
window. If the WDR instruction is not executed inside the window limits, the microcontroller will
be reset.
A protection mechanism using a timed write sequence is implemented in order to prevent
unwanted enabling, disabling or change of WDT settings.
For maximum safety, the WDT also has an Always-on mode. This mode is enabled by program-
ming a fuse. In Always-on mode, application software can not disable the WDT.
11 selectable timeout periods, from 8 ms to 8s.
Two operation modes
Runs from the 1 kHz output of the 32 kHz Ultra Low Power oscillator
Configuration lock to prevent unwanted changes
– Standard mode
– Window mode
XMEGA A3
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