ATmega88PA Automotive Atmel Corporation, ATmega88PA Automotive Datasheet - Page 249

• Manufacturer Part Number: ATmega88PA Automotive
• Manufacturer: Atmel Corporation

9223B–AVR–09/11
Figure 24-1. Analog to Digital Converter Block Schematic Operation
The analog input channel is selected by writing to the MUX bits in ADMUX. Any of the ADC
input pins, as well as GND and a fixed bandgap voltage reference, can be selected as single
ended inputs to the ADC. The ADC is enabled by setting the ADC Enable bit, ADEN in ADC-
SRA. Voltage reference and input channel selections will not go into effect until ADEN is set.
The ADC does not consume power when ADEN is cleared, so it is recommended to switch off
the ADC before entering power saving sleep modes.
The ADC generates a 10-bit result which is presented in the ADC Data Registers, ADCH and
ADCL. By default, the result is presented right adjusted, but can optionally be presented left
adjusted by setting the ADLAR bit in ADMUX.
AREF
ADC7
ADC6
ADC5
ADC4
ADC3
ADC2
ADC1
ADC0
AVCC
GND
Atmel ATmega48PA/88PA/168PA [Preliminary]
TEMPERATURE
INTERNAL 1.1V
REFERENCE
REFERENCE
BANDGAP
SENSOR
8-BIT DATA BUS
INPUT
MUX
ADC MULTIPLEXER
SELECT (ADMUX)
MUX DECODER
10-BIT DAC
ADC CTRL. & STATUS
REGISTER (ADCSRA)
ADC CONVERSION
COMPLETE IRQ
CONVERSION LOGIC
PRESCALER
SAMPLE & HOLD
COMPARATOR
15
+
-
ADC DATA REGISTER
(ADCH/ADCL)
ADC MULTIPLEXER
OUTPUT
0
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