ATxmega128A1 Atmel Corporation, ATxmega128A1 Datasheet - Page 290

• Manufacturer Part Number: ATxmega128A1
• Manufacturer: Atmel Corporation

Specifications of ATxmega128A1

• Flash (kbytes): 128 Kbytes
• Pin Count: 100
• Max. Operating Frequency: 32 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 78
• Ext Interrupts: 78
• Usb Speed: No
• Usb Interface: No
• Spi: 12
• Twi (i2c): 4
• Uart: 8
• 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: 4
• Dac Resolution (bits): 12
• Temp. Sensor: Yes
• Crypto Engine: AES/DES
• Sram (kbytes): 8
• Eeprom (bytes): 2048
• Self Program Memory: YES
• External Bus Interface: 1
• Dram Memory: sdram
• 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: 8
• Output Compare Channels: 24
• Input Capture Channels: 24
• Pwm Channels: 24
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

25.3
8077H–AVR–12/09
Input sources
An integrated temperature sensor is available and the output from this can be measured with the
ADC. The output from the DAC, VCC/10 and the Bandgap voltage can also be measured by the
ADC.
Figure 25-1. ADC overview
The input sources for the ADC are the analog voltage inputs that the ADC can measure and
convert. Four types of measurements can be selected:
The analog input pins are used for single ended and differential input, while the internal inputs
are directly available inside the device. In devices with two ADCs, PORTA pins can be input to
ADCA and PORTB pins can be input to ADCB. For XMEGA devices with only one ADC but with
analog input pins on both PORTA and PORTB, both PORTA and PORTB analog pins can then
be used as input.
The MUX Control registers select which input that is converted and the type of measurements in
one operation. The four types of measurements and their corresponding MUXes are shown in
Figure 25-2 on page 291
The ADC itself is always differential, also for single ended inputs where the negative input for the
ADC will be connected to an fixed internal value.
• Differential input
• Differential input with gain
• Single ended input
• Internal input
Channel 0 MUX selection
Channel 1 MUX selection
Channel 2 MUX selection
Channel 3 MUX selection
to
1-64 X
Figure 25-6 on page
Reference selection
Configuration
ADC
triggers
293.
Event
Channel 0 Result
Channel 1 Result
Channel 2 Result
Channel 3 Result
Register
Register
Register
Register
XMEGA A
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