255
2545M–AVR–09/07
ATmega48/88/168
Figure 23-12. Integral Non-linearity (INL)
• Differential Non-linearity (DNL): The maximum deviation of the actual code width (the interval
between two adjacent transitions) from the ideal code width (1 LSB). Ideal value: 0 LSB.
Figure 23-13. Differential Non-linearity (DNL)
• Quantization Error: Due to the quantization of the input voltage into a finite number of codes, a
range of input voltages (1 LSB wide) will code to the same value. Always ±0.5 LSB.
• Absolute accuracy: The maximum deviation of an actual (unadjusted) transition compared to
an ideal transition for any code. This is the compound effect of offset, gain error, differential
error, non-linearity, and quantization error. Ideal value: ±0.5 LSB.
Output Code
V
REF
Input Voltage
Ideal ADC
Actual ADC
INL
Output Code
0x3FF
0x000
0
V
REF
Input Voltage
DNL
1 LSB
