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7679H–CAN–08/08
AT90CAN32/64/128
Figure 21-1.
Analog to Digital Converter Block Schematic
21.2
Operation
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
ADC CONVERSION
COMPLETE IRQ
8-BIT DATA BUS
15
0
ADC MUL
TIPLEXER
SELECT (ADMUX)
ADC CTRL. & ST
ATUS
REGISTER (ADCSRA)
ADC DATA REGISTER
(ADCH/ADCL)
MUX2
ADIE
ADATE
ADSC
ADEN
ADIF
ADIF
MUX1
MUX0
ADPS0
ADPS1
ADPS2
MUX3
CONVERSION LOGIC
10-BIT DAC
+
-
SAMPLE & HOLD
COMPARATOR
INTERNAL
REFERENCE
MUX DECODER
MUX4
AVCC
ADC7
ADC6
ADC5
ADC4
ADC3
ADC2
ADC1
ADC0
REFS0
REFS1
ADLAR
+
-
CHANNEL SELECTION
GAIN SELECTION
ADC[9:0]
ADC MULTIPLEXER
OUTPUT
DIFFERENTIAL
AMPLIFIER
AREF
BANDGAP
REFERENCE
PRESCALER
SINGLE ENDED / DIFFERENTIAL SELECTION
GND
POS.
INPUT
MUX
NEG.
INPUT
MUX
TRIGGER
SELECT
ADTS[2:0]
INTERRUPT
FLAGS
START