ATXMEGA256A3B-MH Atmel, ATXMEGA256A3B-MH Datasheet - Page 111

• 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. Battery Backup System
10.1
10.2
Features
Overview
•
•
•
The Battery Backup System includes functionality that enables automatic power switching
between main power and a battery backup power.
of the system.
The Battery Backup Module supports connection of a backup battery to the dedicated V
power pin. This will ensure power to the 32-bit Real Time Counter, a 32.768 kHz crystal oscilla-
tor with failure detection monitor and two battery backup registers when the main power source
is unavailable.
Upon main power loss the device will detect this and automatically switch the Battery Backup
Module to be powered from the V
POR and BOR are released, the Battery Backup Module will automatically switch back to be
powered from main power again. The main BOD is used to detect the Vcc voltage levels, and
this must be enabled for the power switching to work.
The 32-bit Real Time Counter (RTC) must be clocked from the 1 Hz or 1.024 kHz output of a
32.768 kHz crystal oscillator connected between the TOSC1 and TOSC2 pins when running
from V
the XMEGA A Manual.
Battery Backup voltage supply from dedicated V
Automatic switching from main power to battery backup power at:
Automatic switching from battery backup power to main power:
– One Ultra Low-power 32-bit Real Time Counter
– One 32.768 kHz crystal oscillator with failure detection monitor
– Two Battery Backup Registers
– Brown-Out Detection (BOD)
– Device reset after Brown-Out Reset (BOR) is released
– Device reset after Power-On Reset (POR) and BOR is released
BAT
. For more details on the 32-bit RTC refer to the “32-bit Real Time Counter” section in
BAT
pin. After main power has been restored and both main
BAT
Figure 10-1 on page 112
power pin for:
shows an overview
BAT