ATxmega256A3U Atmel Corporation, ATxmega256A3U Datasheet - Page 114

• Manufacturer Part Number: ATxmega256A3U
• Manufacturer: Atmel Corporation

Specifications of ATxmega256A3U

• Flash (kbytes): 256 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 32 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 50
• Ext Interrupts: 50
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 10
• Twi (i2c): 2
• Uart: 7
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 16
• Adc Resolution (bits): 12
• Adc Speed (ksps): 2000
• Analog Comparators: 4
• Resistive Touch Screen: No
• Dac Channels: 2
• Dac Resolution (bits): 12
• Temp. Sensor: Yes
• Crypto Engine: AES/DES
• Sram (kbytes): 16
• Eeprom (bytes): 4096
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.6 to 3.6
• Operating Voltage (vcc): 1.6 to 3.6
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 7
• Output Compare Channels: 22
• Input Capture Channels: 22
• Pwm Channels: 22
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

8331A–AVR–07/11
When the BOD is enabled and V
9-4), the brownout reset is immediately activated.
When V
MCU after the timeout period, t
The trigger level has a hysteresis to ensure spike free brownout detection. The hysteresis on the
detection level should be interpreted as V
The BOD circuit will detect a drop in V
ger than t
Figure 9-4.
For BOD characterization data consult the device datasheet. The programmable BODLEVEL
setting is shown in
Table 9-2.
Notes:
The BOD circuit has three modes of operation:
• Disabled: In this mode, there is no monitoring of the V
INTERNAL
TIME-OUT
1. The values are nominal values only. For accurate, actual numbers, consult the device
2. Changing these fuse bits will have no effect until leaving programming mode.
CC
BOD
BODLEVEL[2:0]
RESET
increases above the trigger level (V
datasheet.
.
V
CC
Brownout detection reset.
Programmable BODLEVEL setting.
111
110
101
100
011
010
001
000
Table
9-2.
(1)
TOUT
CC
, has expired.
decreases to a value below the trigger level (V
V
BOT-
CC
BOT+
only if the voltage stays below the trigger level for lon-
t
= V
BOD
BOT+
BOT
V
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
Atmel AVR XMEGA AU
BOT
in
+ V
Figure
HYST
CC
/2 and V
level.
9-4), the reset counter starts the
V
t
TOUT
BOT+
BOT-
= V
BOT
Unit
- V
V
BOT-
HYST
in
/2.
Figure
114