Rainbow Electronics ATmega128L - Manual (Page 222)

222
ATmega128(L)
2467B–09/01
Figure 107. Analog to Digital Converter Block Schematic
ADC CONVERSION
COMPLETE IRQ
8-BIT DATA BUS
15 0
ADC MULTIPLEXER
SELECT (ADMUX)
ADC CTRL. & STATUS
REGISTER (ADCSRA)
ADC DATA REGISTER
(ADCH/ADCL)
MUX2
ADIE
ADFR ADSC ADEN
ADIF
ADIF
MUX1 MUX0
ADPS0 ADPS1 ADPS2
MUX3
CONVERSION LOGIC
10-BIT DAC
+
-
SAMPLE & HOLD
COMPARATOR
INTERNAL 2.56V
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
GAIN
AMPLIFIER
AREF
BANDGAP
REFERENCE
PRESCALER
SINGLE ENDED / DIFFERENTIAL SELECTION
AGND
POS.
INPUT
MUX
NEG.
INPUT
MUX
ADHSM