Data Sheet

246
ATmega48A/PA/88A/PA/168A/PA/328/P [DATASHEET]
Atmel-8271H-AVR- ATmega-Datasheet_08/2014
Figure 24-9. ADC Power Connections
24.6.3 ADC Accuracy Definitions
An n-bit single-ended ADC converts a voltage linearly between GND and V
REF
in 2
n
steps (LSBs). The lowest
code is read as 0, and the highest code is read as 2
n
-1.
Several parameters describe the deviation from the ideal behavior:
 Offset: The deviation of the first transition (0x000 to 0x001) compared to the ideal transition (at 0.5 LSB).
Ideal value: 0 LSB.
Figure 24-10. Offset Error
GND VCC
PC5 (ADC5/SCL)
PC4 (ADC4/SDA)
PC3 (ADC3)
PC2 (ADC2)
PC1 (ADC1)
PC0 (ADC0)
ADC7
GND
AREF
AVCC
ADC6
PB5
10µH
100nF
Analog Ground Plane
Output Code
V
REF
Input Voltage
Ideal ADC
Actual ADC
Offset
Error