ATXMEGA256A3B-MH Atmel, ATXMEGA256A3B-MH Datasheet - Page 112

• Manufacturer Part Number: ATXMEGA256A3B-MH
• Description: MCU AVR 256KB FLASH A3B 64-QFN
• Manufacturer: Atmel
• Series: AVR® XMEGAr

Specifications of ATXMEGA256A3B-MH

• Core Processor: AVR
• Core Size: 8/16-Bit
• Speed: 32MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Number Of I /o: 49
• Program Memory Size: 256KB (128K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 4K x 8
• Ram Size: 16K 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-MLF®, 64-QFN
• Processor Series: ATXMEGA256x
• Core: AVR8
• Data Bus Width: 8 bit, 16 bit
• Data Ram Size: 16 KB
• Interface Type: I2C, SPI, USART
• Maximum Clock Frequency: 32 MHz
• Number Of Programmable I/os: 49
• 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: 12 bit, 8 Channel
• On-chip Dac: 12 bit, 2 Channel
• For Use With: ATAVRONEKIT - KIT AVR/AVR32 DEBUGGER/PROGRMMRATSTK600 - DEV KIT FOR AVR/AVR32770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPI
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: ATXMEGA256A3B-MU; ATXMEGA256A3B-MU

10.3
10.3.1
8077H–AVR–12/09
Battery Backup Module
Battery Backup Power-On Detection
Figure 10-1. Battery Backup Module and its power domain implementation
The Battery Backup Module consists of the following:
• A V
• A Power-switch for switching power to the battery backup domain between main power and the
• A 32.768 kHz Crystal Oscillator (XOSC) with 32.768 kHz, 1.024 kHz and 1 Hz output.
• A XOSC Failure Monitor for detecting failure on the Crystal Oscillator.
• A 32-bit Real Time Counter.
• Two Battery Backup registers.
The main BOD is used to detect Brown-Out on the main power so this must be enabled for the
power switching to work.
When main BOD is detected, the Battery Backup Module will switch to be powered from the V
pin. When main power is restored and/or the device is reset, software must enable access to the
Battery Backup Module by writing a dedicated Access Enable bit in the module.
The Battery Backup Power-On Detection circuit will set the POD Flag (BBPODF) when power is
connected to the V
TOSC1
TOSC2
VBAT
backup battery power domain. It includes
V
BAT
– A Battery Backup Power-On Detector (BBPOD).
– A sampled Battery Backup Brown-Out Detector (BBBOD).
BAT
pin.
power supervisor that ensures correct operation and detection of falling power in the
supervisor
power
V
BAT
BAT
Registers
monitor
Backup
XOSC
XOSC
RTC
pin.
Power
switch
Programming
Watchdog w/
independent
Internal
Interface
RCOSC
OCD &
RAM
Peripherals
&
CPU
EEPROM
& Fuses
supervision
Oscillator &
FLASH,
controller
power
sleep
Main
XMEGA A
XTAL1
XTAL2
VCC
GPIO
112
BAT