ATTINY26L8SU SL383 Atmel, ATTINY26L8SU SL383 Datasheet - Page 97

• Manufacturer Part Number: ATTINY26L8SU SL383
• Description: MCU 8-Bit ATtiny AVR RISC 2KB Flash 3.3V/5V 20-Pin SOIC T/R
• Manufacturer: Atmel

Operation
1477J–AVR–06/07
Figure 51. Analog to Digital Converter Block Schematic
The ADC converts an analog input voltage to a 10-bit digital value through successive
approximation. The minimum value represents GND and the maximum value represents
the voltage on the AREF pin minus 1 LSB. Optionally, AVCC or and internal 2.56V refer-
ence voltage may be connected to the AREF pin by writing to the REFS bits in ADMUX.
The internal voltage reference may thus be decoupled by an external capacitor at the
AREF pin to improve noise immunity.
The analog input channel and differential gain are selected by writing to the MUX bits in
ADMUX. Any of the 11 ADC input pins ADC10..0, as well as GND and a fixed bandgap
voltage reference of nominally 1.18V (V
the ADC. A selection of ADC input pins can be selected as positive and negative inputs
to the differential gain amplifier.
If differential channels are selected, the differential gain stage amplifies the voltage dif-
ference between the selected input channel pair by the selected gain factor. Note that
the voltage on the positive input terminal must be higher than on the negative input ter-
ADC10
ADC9
ADC8
ADC7
ADC6
ADC5
ADC4
ADC3
ADC2
ADC1
ADC0
AREF
VCC
GND
8-BIT DATA BUS
REFERENCE
INTERNAL
INTERNAL 1.18 V
2.56 V
REFERENCE
INPUT
INPUT
POS.
NEG.
MUX
MUX
ADC MULTIPLEXER
SELECT (ADMUX)
MUX DECODER
+
-
BG
GAIN
AMPLIFIER
DIFFERENTIAL SELECTION
), can be selected as single ended inputs to
SINGLE ENDED /
10-BIT DAC
ADC CTRL. & STATUS
REGISTER (ADCSR)
ADC CONVERSION
COMPLETE IRQ
PRESCALER
CONVERSION LOGIC
ATtiny26(L)
SAMPLE & HOLD
COMPARATOR
+
-
15
ADC DATA REGISTER
(ADCH/ADCL)
MULTIPLEXER OUTPUT
ADC
0
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