ATxmega256A3BU Atmel Corporation, ATxmega256A3BU Datasheet - Page 355

• Manufacturer Part Number: ATxmega256A3BU
• Manufacturer: Atmel Corporation

Specifications of ATxmega256A3BU

• 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: 47
• Ext Interrupts: 49
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 8
• Twi (i2c): 2
• Uart: 6
• 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

28.3.2
28.3.3
8331A–AVR–07/11
Differential input with gain
Single ended input
Figure 28-2. Differential measurement without gain
When differential input with gain is enabled all input pins can be selected as positive input, and
input pins 4 to 7 can be selected as negative input. When the gain stage is used, the differential
input is first sampled and amplified by the gain stage before the result is fed into the ADC. The
ADC must be in signed mode when differential input with gain is used.
The gain is selectable to 1/2x, 1x, 2x, 4x, 8x, 16x, 32x and 64x gain.
Figure 28-3. Differential measurement with gain
For single ended measurements all input pins can be used as inputs. Single ended measure-
ments can be done in both signed and unsigned mode.
The negative input is connected to internal ground in signed mode.
ADC0
ADC1
ADC2
ADC3
ADC4
ADC5
ADC6
ADC7
ADC4
ADC5
ADC6
ADC7
ADC0
ADC1
ADC2
ADC3
ADC4
ADC5
ADC6
ADC7
ADC0
ADC1
ADC2
ADC3
1/2X
Atmel AVR XMEGA AU
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