ATtiny261 Atmel Corporation, ATtiny261 Datasheet - Page 143

• Manufacturer Part Number: ATtiny261
• Manufacturer: Atmel Corporation

Specifications of ATtiny261

• Flash (kbytes): 2 Kbytes
• Pin Count: 20
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 4
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 16
• Ext Interrupts: 16
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.12
• Eeprom (bytes): 128
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

15.3
2588E–AVR–08/10
Operation
Figure 15-1. Analog to Digital Converter Block Schematic
The ADC converts an analog input voltage to a 10-bit digital value through successive approxi-
mation. The minimum value represents GND and the maximum value represents the voltage on
V
The voltage reference for the ADC may be selected by writing to the REFS2:0 bits in ADCSRB
and ADMUX registers. The VCC supply, the AREF pin or an internal 1.1V / 2.56V voltage refer-
ence may be selected as the ADC voltage reference. Optionally the internal 1.1V / 2.56V voltage
ADC10
AGND
CC
ADC9
ADC8
ADC7
ADC6
ADC5
ADC4
ADC3
ADC2
ADC1
ADC0
AREF
VCC
, the voltage on the AREF pin or an internal 1.1V / 2.56V voltage reference.
8-BIT DATA BUS
INTERNAL 2.56/1.1V
INTERNAL 1.1V
TEMPERATURE
REFERENCE
REFERENCE
SENSOR
REGISTER B (ADCSRB)
ADC CTRL. & STATUS
INPUT
POS.
MUX
INPUT
NEG.
MUX
ADC MULTIPLEXER
MUX DECODER
SELECT (ADMUX)
DIFFERENTIAL SELECTION
SINGLE ENDED /
+
-
GAIN
AMPLIFIER
10-BIT DAC
REGISTER A (ADCSRA)
ADC CTRL. & STATUS
MUX
ADC CONVERSION
COMPLETE IRQ
CONVERSION LOGIC
PRESCALER
SAMPLE & HOLD
COMPARATOR
+
15
-
ADC DATA REGISTER
MULTIPLEXER OUTPUT
(ADCH/ADCL)
ADC
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